SS Rider'z

Okay so here the deal.. Im Currently about to buy a New C5 CF DF Clutch & throwout Bearing from this dude on craigslist for 350.. Is This A Good Price?? Well i've jus rebuilt my M6 with Tick Performance, so im replacing everything but the thing is i beleive the C5 Clutch is a 12". Will this work on my stock flywheel?? Here are some pics of the clutch