I have a 2003 wrx sedan looking for $500 with the trade of a stock ecu. Holds at 17 psi. 265 hp. I Paid $700 including shipping. You can look all the info at Vishnutuning.com
I told them i had intake exhaust when i got it, which was last fall. It can be tuned as long as the same software is used. what mods do you have?.