Things like this have happened to me on eBay from time to time, albeit on a smaller scale. Item I won and paid for suddenly cannot be found. Buyer turns out to be an 8-year-old boy using grandma's computer (or so I am told). On the other hand, I once took a chip to a club meeting and it traded away, then I realized it was still a live auction that sold; had to explain to the buyer that the chip is gone, and refund his money.

In this case, I suspect the seller was not the actual owner of the chip-box; grandma or someone heard of it and took the goods back. Or maybe cops raided the pawnshop for stolen goods!

Perhaps you'll come across the Grand Prix collection again, somewhere. Meanwhile 10,000 thanks for the four SOURCE OF 10,000 PRECIOUS THINGS Chinese chips sold to me at a most reasonable sum in Sacramento. And for that tip about SMILE!