Great find and good deal!
The seal is a sticker, not a stamp. It's red instead of today's blue or black and appears to have some of the adhesive bleed-through common with 20-year old stickers. The box is the 1992-to present style. One fast way to tell? The front is printed with two colors. Bees, until the 100th anniversary of the brand in 1992, had tuck boxes printed in one color, either red or blue on the white cardboard.
USPC made these backs with the joker bee in the middle 1990s. A company that produces "casino nights" in Louisville here used these decks regularly. They are the casino quality Bees we all love and come in red and blue. They may very well have been casino samples or premiums, but I will leave more sleuthing to others. I have several mid-90s of these in my collection. IIRC, I bought them at the USPC Norwood store. And, I do have a brick of 1962 or before sealed Bees for sale, if interested.
Chris Turner (aka Andrew Daugherty on the forum, yes with an "A".)
52 +J and CPCC
Jeffersonville, Ind.