Well dosnt need new rings exactly, just would if I ran 10 pounds of boost through it would be up for a rebuild.
Heads been rebuilt tho and 184 across all four cylinder which isn't far from stock. Little bit of build up but hey she's 23 years old

I got my halfcut through a mate who ownes a tuning shop up here called High Tech Tuning.  He goes over to Japan all the time and sources engines, import parts and cars which I felt comfortable about. 
He also tested the engine in my halfcut before passing it on and I havent had a major problem with it since (touch wood) and that was nearly three years ago. 
Not sure where you are but maybe try Gorilla Industries or PM some of the others guys who have done swaps.  Artymr2, Darius, Bionikal...

Buy a turbo one then sell yours.  This way you can wait until the perfect one becomes available and also swap over any OEM parts from your current car that are in better condition plus aftermarket parts etc.
Too much hassle doing engine conversions I reckon these days as the factory turbo or already converted cars are cheap and mechanic hourly rates are high to have the conversion done to your own car.
My 2c

Oh i've been named again? Thanks Dudeman
 
Personally, the choice was easy for me.
1. I'd had the car from almost new, 11yrs
2. engine hit 200,000kms, i was going to take it out and get someone to rebuild it anyway
3. It recently had a respray with all the bodykits and ICE units
4. and a perfect 3/4cut came on the market for about $6K (thanks MR2QIK) i was going to spend half of than anyway on the rebuild.
 
In spare parts alone i got back what i paid the mechanic (thanks Senor_2)
 
Added a few parts here and there to get to where i want.