A 95-97 model WRX bar will go strait on. I'm pretty sure that was the model. There is just a small gap at the sides near the side fenders, but you can pump your guards to suit. I know that an 90ish model Integra bar comes close - I am using one on my TRX, with only very minor mods. If you can chase a custom bar from a drift spec Toyota Cresida in Japan or some were else they will go strait on, just a few gaps at the side. I know that a Nissan Leopard bar can be fitted easily as well as a Nissan Lorell Bar.
I am using an S13 bar, the front of the bar sits in fine, but the sides are a mile out and have to be moded. I do know that the S15 bar is very close fit, more than the S13. WRX is the way to go, If I knew it before I would have saved myself the hassel, but Im happy with my Bomex bar.