"there wouldn't be any guarantee would there that this is an obsolete
chip?"

I don't think you understand!!!
How can it be an obsolete chip, if it was never made. At best, 10 of these chips were made and all notched. It is a Sample. I bet there are Chipco notched samples of all Mirage denominations. Chipco bid on the opening rack at the Mirage. They got the high roller roulette chips, only.
Below is a notched sample of the roulette, I have 11 different colors and designs. The difference here is, the chips were produced. I have several different colors with table wear.