I was interested in the same question. I did some research, and posted my findings on the ChipBoard. At the time, I got no responses.

In summary, I think the ROULETTE mold was created by Paul-Son to adhere to Atlantic City gaming regulations, and they introduced it around 1980.

http://www.thechipboard.com/archives/archives.pl/bid/399/md/read/id/1657023/sbj/is-this-the-first-paul-son-roulette-chip/

I would be interested knowing what you and others think of my evidence/argument.