Alright I'll put my 2 cents in too
It is a problem with the supercharger that can be rebuilt and without looking at it, I'll take a wild guess. It probably ran hot and was either out of oil, or short of oil, and seized. I would say no warranty.
The buyer would have to send it to Rotrex for a rebuild and it would probably be cheaper to buy a new one as I think this one is toast.
But that being said, I'll giver a firm offer of $500 + shipping, just for the parts and I'll assume the risk of the damaged supercharger.
I can rebuild it