I got these yesterday and I was wondering if this was a common thing that was done with TRKs where they actually serialized the higher denom chips if a customer asked to do so. These chips in particular that are shown are 1000s. There are other chips in the set; 5, 10, 20, 50, 100, 500, 1000 (that might of been it I'll have to double check). The 500s and 1000s in the set have the serialized hot stamp on them and as you can see from this picture the numbers range pretty widely so there's a somewhat large number of these out there, I can double check on the too.

My main question though is, was this something that was done regularly? I didn't even know that TR King did this until I saw these, unless these were done by someone after the chips had been shipped and arrived with the customer.

Maybe its something if we can possibly find the order card, but I had Luke Rapley try to find some information and he wasn't able to find much. The only information he was able to find was this:
"The only information I can find on these chips is the name Pedro Flores Gomez and being ordered in 1971. I am not sure if these are personal chips, from an approved card room, or from an illegal club."

It's very interesting though and unique I think. Enjoy!