All these stories remind me of the Twin Towers issue. Some of those indeed followed the same "shortage of Santas" routine.

One casino I know of, in order to be fair to the customer, continually had to re-order additional "Twin Towers" in order to keep equal amounts of the other designs in the machine.
Without giving away numbers let's just say there are over 1000 more TT's than the other designs.

That doesn't mean, though, that the TT from other casinos won't remain the harder one to find.