"I bid more, but the top bidder bid more than $450, and still didn't meet the reserve"

I would be leery of paying that much for an illegal chip.
These things exist somewhere. IMO they will eventually come out. Even if it was not used in gaming it is a desirable chip for us.

There are at least two chips missing from most KY collections. Blue KY Club and Stardust $500.
Several of the Blue showed a couple years ago and they went high. I layed off until the next time they show.
I will be coming home in April. I'll see what else I can dig up on the Stardust.