Thanks to others on this board, I've had the pleasure of seeing the 3 W's, Big Showdown, and The Challengers. All three are good games, and it's a shame the first two on the list only exist in very small numbers now.
While the likelihood would probably be small, it could be possible that at least some of the episodes may have been preserved - episodes of the CBS version of The Jokers Wild were found a few years ago in at a station's storage area, and episodes of The Hollywood Squares - also thought gone - were found mislabeled while searching for the show Dark Shadows. That said, the odds would be slim.
As for The Challengers, I'd love to see it again, however, it's one of those shows that just doesn't lend itself to reruns, and game shows just don't seem to be a cost-justifiable product for television DVDs. Which is a shame, it truly is, as I enjoyed this show a lot.
A warm welcome to you, Mr. Greenberg.