You said you had the clutch replaced, does that mean he put in a new pilot bearing and reinatalled the trans? if so he must not have been too worried about it, have you driven it, does it make any noise. That bearing should fit the input shaft without any pressure to install, but its there to keep the input shaft inline with the clutch disk, if its worn real bad, when you push the clutch down, the disk can get off center, causing the input shaft rear bearing to fail. The input shaft can be replaced lots cheaper than buying a used trans.