I have a Perrin dual exhaust for 08+ WRX/STi sedan. 3" stainless all the way through, 4" slash cut tips, gaskets and bolts included.
Here is a link to the Perrin website where you can see how much it costs new ($945 + tax and shipping). perrinperformance.com/i-13324009-cat-back-exhaust-system-for-2008-14-wrx-sedan.html
Also fits 09-13 FXT
Here are pics of the actual exhaust in my garage: