hmm 2nd hand clutch... trust is such a big word because the work involved to install a clutch is not cheap... so it comes down to the cost/benefit of doing this...

I dunno, make sure it is from a reputable guy and when he/she tells you it has done 50K or so then add another 20k to that hahaha... then do your maths...given that an average clutch lasts 100k-120k