In old cars, air con mechanics usually always insist on replacing the evaporator at a cost of $2000, that's why I always do it myself. For an old system that has has major work done (like replacing parts) they should do an evacuation of the oil and also do a pressure test. Just refilling it and seeing if it works is probably not the best way to do it, but I'm not an expert or licensed so I still leave it in the hands of someone else to do the final part of the work. Sounds like you had a real bad experience dudeman. 

mr2y
In old cars, air con mechanics usually always insist on replacing the evaporator at a cost of $2000, that's why I always do it myself. For an old system that has has major work done (like replacing parts) they should do an evacuation of the oil and also do a pressure test. Just refilling it and seeing if it works is probably not the best way to do it, but I'm not an expert or licensed so I still leave it in the hands of someone else to do the final part of the work. Sounds like you had a real bad experience dudeman. 

My car had already been changed to the new gas when I purchased her, but it doesn't work.  Haven't really worried about it.  My mechanic started doing A/C stuff a few months ago, so I asked him to check it when I had a service done.  He gassed it, worked out that it was the compressor, took the gas back out & didn't charge me anything.  He's a good guy.  Stewy from Charlestown steering.
 
I can live without A/C for a bit longer. 

Carmikey
Just to clarify dudeman, was that "Steve from Macarthur Automotive Air Conditioning in Bargo, NSW?".....I luv it!!

So sick of so called professionals / tradies doing crappy dodgy jobs & rapping everyone, enough is enough!

Well, Steve from Macarthur Automotive Air Conditioning in Bargo, NSW, was local to me and I thought it would be good to support a local business. I was going to use a 2nd hand air con compressor, but Steve from Macarthur Automotive Air Conditioning in Bargo, NSW insisted that a brand new model was the way to go, because if the old unit failed I would have wasted the labour and regas costs involved. So I thought yeah ok, I intended to keep the car long term and wanted it perfect. 
 
I started to smell a rat when I showed him the green dye that had leaked out, this was pointed out to me by my mechanic. Steve from Macarthur Automotive Air Conditioning in Bargo, NSW, swore blind it was coolant, but I don't know why coolant would leak from an aircon compressor. 
 
Anyway, enough of the thread hijack, and if anyone was confused, I was totally unsatisfied and felt like I wasted $12~1300 by having work done by Steve from Macarthur Automotive Air Conditioning in Bargo, NSW. For from being slanderous or defamatory, this was my personal experience in dealing with Steve from Macarthur Automotive Air Conditioning in Bargo, NSW, and I would not try to stop others spending their hard earned money and trying him out with anything else than a simple regas and share their experience. 

I can confirm that the following part numbers do NOT fit a 1993 mr2 turbo....
88515-60210 (Toyota part)
447500-2370 (denso - equivalent to above) - the 6mm bolt holes on one side taper to 5mm so you can't put the holding bolts through.
447500-9052 (denso) - the recess lip for fitting against the plates/orings on the evaporator is not deep enough to form a seal.

The old part number from a mates car is 047500-9071. However the part has been discontinued / superseded. Other part numbers given have been discontinued. Auto shops seem to have little knowledge than looking up a book that gives the above part numbers. I should have it sorted in the next day, swapping parts / ordered other part numbers.... I will post up the new part number once I have it.

My advice after seeing the condition of aircon parts in a mr2, take the time yourself, before re-gassing get the system degassed, replace all the orings with new green orings ($30), raplace the drier ($30), remove the evaporator and clean with soapy warm water / gentle hose (allow hours to do this), clean fan and ducting around evaporator, replace the a/c Tx expansion valve ($50-$75 once I find the right part number), if your super keen remove the a/c compressor for service of new oil ($75), new belt ($15) and then regas (under $200).
So all up, doing it yourself $475 parts/srvice. Labour for me approx 2 hours replacing all o-rings, 30 mins replacing drier, 4-6 hours on evaporator/Tx valve in and out plus clean, 2 hours remove and refit compressor/belt after sevice.

Ashdown-Ingram seem to have all the components and parts of an a/c system. Never heard of them before but will remember now.
I am awaiting a part from super cheap as they didn't want to refund the wrong part that was ordered, wanting to replace with another part. See what happens when I get this next part.
I also found a a/c specialist who has the superseded part but wouldn't give me the part number.
With the link to ashdown-Ingram I am confident this will soon be solved.

Ok found this information from searching the internet and various catalogues:
 
SW20 12/1991 - 8/1993 - R12 evaporator 210x245x90 - Denso 047500-1730
SW20 9/1993 - 11/1999 - R134a evaporator 207X242X92 - Denso 447500-9052
 
It seems you and I both might have the R12 core (I know I definitely do because I measured it)
So far it looks like autofrost.com.au has been the most helpful:-
 
R12 core TX valve - http://www.autofrost.com.au/store/index.php?route=product/product&product_id=753
R134a core TX valve - http://www.autofrost.com.au/store/index.php?route=product/product&product_id=819
 
Please don't take this as gospel just yet, I'm just reporting my findings...
 
Edit: here are the dimensions of my R12 evaporator core (approximate): 210x245x90
The R134a core is roughly: 207X242X92
(added to the part list above)

Yep have read the Internet, all the listings and unfortunately I have purchased multiple parts that list as a mr2 however they are not - see the pics. My misfortune from buying eBay where it costs more to return than your money back - hence why I am posting my experience so others don't waste money.
The picture attached shows the ugly looking one on the front right (dead out of my car), the front left one out of another club members car who's tried to help, then the other parts purchased in the background, with the left one wrong ridge/lip size, and the right one wrong bolt hole size.
The denso 447500-9052 has the incorrect size ridge / edge for forming a seal / sitting against the evaporator plate/joiner.
Yes you need the Tx expansion valve for the type of gas you are running cause the gas behaves differently. Some of the part numbers are discontinued/superseded because of the change in Australia to only the new gas being sold (legally).
I will upload when I have found the correct replacement part.

Solution- early 1993 mr2 turbo sw20 air condoning replacement Tx expansion valve for leaking air conditioning. This is for Tx a/c expansion valves with a recessed lip and 6mm bolts as per previous pictures. There are different Tx valves for mr2 sw20s.

The 1993 car was designed for the old gas. Toyota recalled the mr2 of 1993 because of faulty Tx expansion valves in high heat / high humidity, so the part was listed as discontinued.

The new a/c gas molucules are smaller, so Tx expansion valve internal seals were redesigned, however unknown part number for the mr2 to this point. Apparently you can still use the old Tx valve designs, there is a possibility the gas at an incredibly small amount can leak past the internal seal. Apparently it's a molucules amount and the gas stays within the system, just that it can go past the internal Tx valve (stressed that it's a molucule amount) and doesn't effect the heating/normal air running past the evaporator.

Supercheap auto assisted me with their supplier of jayair products. The supplier has the original part design (old gas design) denso 047500-9071 aka TX9070. Supercheap auto can order it from the supplier. Cost was $55.

That was my experience in trying to get a fitting part. Should anyone come across the part number of the new gas style valve Tx expansion a/c valve that has a recessed lip, please post up for future readers.