Talk to Pete, 6MTizzle... I think the one he has will fit yours. I should have bought it but ended up buy something else.
running a cobb cbe, a similar downpipe to the one I'm selling, and the cobb stage 2 map my car put down 263whp and 286tq on DB's dyno. The power hits so much sooner with a downpipe and pulls harder the whole way to 7k. mad powa!
I've got a Crucial coated TurboXS Stealthback (4" downpipe to 3" piping with high-flow cat). This works even with your stock STi axle back and adds power.