I don't think I've ever seen a spun cam bearing. Repairing that, if it's actually the case, would be extremely expensive. Even a spun main bearing would make me think twice about accepting the engine as a gift, let alone paying anything for it, or even traveling very far to pick it up.
Jerry

"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway
Love your enemies and drive 'em nuts!