I may have some examples. Some of the older casinos have chips for sale. One example is the Four Queens. They have some older 50 cent chips and up and the cage is very nice and will look thru what they have for you.

Same goes for the Riviera. They use to have racks of Silver Strikes I could look through but not anymore.

Recently Lucky Club sold me old Speedway chips they had in the cage, but those are gone as well.

The Golden Gate also has older chips in the cage. They were always beat to crap, but one day I got lucky and got two L value chips for face that looked uncirculated.

My best advice is to hunt around and ask. You don't know if you don't try. It is best at times when the cage is not busy. Also a tip goes a long way. Sometimes I make it known before hand that I tip with either a comment or hold some money in my hand and a few singles as well.