I know what your talking about as I have both of them sitting on a storage shelf while I refurbish the cab. They do indeed look like wet dry vac nozzels. To answer your question I don't think I've seen them in any catalogue and are rare pieces. When I took them out there was a piece of an ice scrapper stuck in one which probably came from the original Chev Pontiac Dealer as it had the old Pontiac Indian Head logo on it.
Bob T
