Here is one that I can guarentee there is only 52 in existence. All are UNC.
TCR lists how many exist. But it does not have a listed price.
I watched them being destroyed and have a copy of the destruction order.
There is only 83 of the $100.
There are only 256 of the $25.
IMO, if someone wanted $500 chips, they could get them for $500.