Anyway, to answer your question in the thread title, I don't know if there was a market at all.
All I saw was "hey, Small Greek Key", and "hey, small price" so I thought I'd fire off an e-mail. Most likely what would have happened is I put it on the pile of things that require milling while I kept my eye out for other small or large Greek Key hot stamps to add on. More of a curiosity than anything else.
I don't know if casinos have used the Greek Keys for a long period of time.