I doubt that you will ever see any of the money. This dude is just fishing to see if there are any buyers out there at his prices. Maybe he got stuck with a pile, and he's trying to offload it on someone else.
Do you know for sure there were PL coins minted specifically for that denomination? If so then if you think it is worth what you specify get it slabbed. ICCS would be able to tell you if it is legit.