2002 V70 T5 3" down pipe / cat back exhaust

[Gribs]

One of my mates is looking into tuning his V70 and asked me for help as I've previously had a couple of modified cars, most recently a stage 3 Saab 9-5 Aero. From what I can see ~320 bhp seems easily achievable with a 3" down pipe and cat back, plus a remap. However it all seems very expensive compared to what I'm used to. Is this just a Volvo thing or are there reasonably priced parts available and open source remapping?