Motorcycle Repair: 81 Honda CM400, honda dealer, 5k miles

Question
I am thinking about purchasing an 81 Honda CM400. The bike has 5k miles, but isnt ridable due to "the camshaft holder does need to be replaced the part can be found online but i do not have the time to fix it, the part is around $74 new" described by the seller. His explanation was that a rock flew up and hit the bolt, then the "holder" broke due to stress. Does this sound like a simple part to find/fix?

Answer
That would have had to be quite a whack with a rock.  It's not a hard fix but I'm not sure if the parts are still available. I'd recommend you check with the honda dealer to make sure all of the parts are still available.  The rock story doesn't make a lot of sense to me but I wasn't there.

Regards
Rich