Those are getting tougher to come by.

Ironically, the highest denomination, the red $100, is the most abundant, and for year was the only one available.

The $1 and $5 denominations are hard to find, but pop up every now and again for usually a couple hundred dollars each. Still difficult.

The black $25 is a relative newcomer, and the most expensive. HOWEVER, it is not "rare" as the current seller has a few dozen of the chips. The problem is, he is the ONLY seller of the chips and is in no hurry to sell. It'll list for $650 and sit for months and that seems fine for the seller.