There's been an odd run of "cheap" Pong consoles on eBay these days. Usually these are wildly overpriced (and there are still plenty of listings like that) but some of these aren't too bad.
There is something about Pong consoles that is nothing like other consoles. The game is so simple, but very addictive. Crazy to see the games we have now when comparing them to something released just under 50 years ago.