For the Electronics Buff who has everything

LOL. Check out what the same seller has on offer. Nixie tubes, paper capacitors, valves etc. A treasure trove of museum pieces.

That's actually valuable stuff to the right people: The valves, paper in oil caps, vacuum relays and the teflon caps are all in high demand by radio amateurs (who usually just hoard it all until they die) and audio constructors for projects.

The paper caps are also in huge demand for radio restorers. The current state of affairs is to replace the existing paper caps that have been eaten by rats, and replace them with modern (bright yellow!) polys. Not a nice look.

As such, if you can get a functioning paper cap that hasn't been made a meal of, that's worth much more.