In the US? The STi has been at dealers since March of 2003, I think.
Edit: 2004 Model

 

Nope.

 

In the 90s? umm performance wise? what car? can you be a bit more specific?

 

I would say the 97+ 2.5rs was probably the closest thing to decent performance in the states from subaru.

 

Even then you'll have to do a lot of work to get it near WRC performance. STi has been available since 1996 overseas.

 

Early WRC Impreza was pretty similar to production car.
To make, Gr.A WRC Impreza you can get 93-96 any AWD 4dr Impreza
Get a front clip of WRX STi from Japan or Europe.
Swap front bumper, hood, and engine.
You are pretty much done.

To make later model GC8, its harder because the body is wide in WRC. Starting from 2dr 99-01 2.5RS is a good idea. The WRC headlights are same as 97-97 Impreza. Again you need to swap engine because the turbo motor was never here on GC8

 

go buy a wrc car