So I'm pretty fed up with the bearing noise from my A/C compressor (confirmed, spun pulley while belt was off) and don't have the $$ to fix everything before MTC so I've decided to just ditch it for now and put it back later. My alternator is in the FWD position like Celica since my engine came from a Caldina so the same belt is used to spin the alternator.
 
Initially I thought maybe I could just run a smaller belt but the issue is that without the A/C compressor in the system the idler pulley will be spinning in the opposite of direction which is no problem but the belt will be running on the grooved side to the flat surface of the idler. Is that ok?
 
I suppose my other option is to re-locate the alt to bottom position but I like it better up top as no oil can possibly leak on to it (unlike old engine) even if the trade off is difficulty to access thermostat...

So I've made quite a progression, thought it'd be useful for those that might tackle this in the future...
 
Stock idler pulley

 
 
Solution: bought Nuline pulley kit "Hyundai Excel no A/C" as it was the closest I could find to suit my application. It's a 4 ribbed pulley for a 5 ribbed belt and it comes with the spacer just like the stock pulley.
 
Problem (reversal haha):  The new pulley + new spacer does not fit stock adjustment bolt (bore too small). Spacer also needs retangular part cut off to make it "OEM style".


 

 
Option 1: Find a bearing with the same inner bore size as stock spacer/bolt that fits the new pulley. Being a 11mm bore size it was unique and had no luck even after going to a couple bearing shops. Mission aborted.
Option 2: Drill the new spacer with 11mm drill bit. Mission accomplished. (Thanks Ken for letting me use workshop at 5 am lol
The Nuline pulley kit cost me $61, drill bit $16 and belt is roughly $25 just to give an approx. cost guide
 
Option 3: http://www.fensport.co.uk/Parts/Model_19/Category_1/26 - another viable alternative, direct fit, less muck around
 
Now all I need to do is find a belt that fits! Once I've found it, will update this thread. Oh and Merry Christmas!

That would have been a very nice Christmas gift TDB thanks for being so generous :)
Drove to Repco this morning without the belt. Drove home with the belt :D
Part number is 5PK1050.