If you are getting a turbo, then get the exhaust that you want for the turbo kit and fabricate a way to hook it up to your car. I have the same swap as you and I made my own 2.5" exhaust:
- 2 mandrel U bends
- 1 6 foot length straight pipe ( they only had 6 foot lengths)
- 2 butt flanges ( not necessary but I want to be able to remove the cat)
- 1 spring flange (I can't remember what this is actually called but it goes right after the header and compresses around the donut seal)
- 1 borla 2.5" muffler
- 1 nice 3" tip
- 1 magnaflow high flow 2.5 inch cat
- 1 mig welder
- 2 cans of high temp exhaust paint
- 1 3 foot length of 1/8 hot rolled steel rod (for hangers)
Just cut the u bends to match the angles of your stock exhaust, use the straight pipe for the main section, weld the cat towards the front of the exhaust, so forth and so on, if you really want to do this i'll write up a better discription if you so need but it looks great on my car.