The fact that you control the market doesnot make an item rare. The fact that you have 1000 of them, and are theoretically releasable as single units causes them to not be 'rare'. They may be hard to obtain, the market might be restricted, either of which may create value, but neither causes rarity. Since they are 'new' to the marketplace, they are uncommon. But the justification for using the word 'rare' does not meet the definition of rare.

I am still curious about how the chips could have made their way to you without the consent(hence the release) of the casino. I find it strange that a casino exec would give out a company asset with a possible valueof several grand (not sure what a drink costs at that particular establishment).