I bought an individual set of these 6 chips from an ebay seller "elitechips" a while ago.

It appears that he is now selling them in bulk, in sets of 500 per lot, with prox. 150 sets available if I read his current auctions correctly. That's a LOT of chips, which seems to indicate a former substantial-sized gambling operation. I tend to believe these were used at Canadian charity gambling venues a while back, as the seller claims.

FYI, see his current & recently closed ebay auctions at:
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=2108198424
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=2102729258

Further info: The insert patterns and inlay styles are consistent with Paulson non-public patterns. That is, Paulson will only sell certain insert styles to the general public, including the fantasy styles they sell in their retail store. Other color/size combinations are reserved for liscensed operators, like these. Also note that the $20 chip is true black. It's my understanding that Paulson doesn't sell black chips to the general public (only charcoal gray).

And finally, if you look at these chips under black light, you will see a UV marking that repeats: "CPIAAQ". This is typical of liscensed-type chips.

FYI, I looked up CPIAAQ thru a search engine and found that is a french acronym for a Quebec government board that promotes agriculture industries. The name is: CPIAAQ = le Centre de promotion des industries agroalimentaires du Québec
Perhaps this was the oversight board for the charity casinos in Quebec at that time? It also may explain the graphic on the chips - which appears to be a staff of wheat.

Perhaps that's more than you wanted to know??