Easiest parts to use would be a 2006 STI trans with new STI front axle seals, and an STI clutch and flywheel combination. You'll need a driveshaft from a legacy 2.5i and a controller for the dccd (ie spiiders).

These aren't the parts I used but they'd be the easiest.

Hey bro.. could you tell me what parts you used for your tranny swap? Im getting ready to do one and dont know what to get to make the swap as easy as i can. Or could you point me to the right thread?