The mold you refer to is called a "house" mold, because it refers specifically to the casino in which the chips are to be used. Paulson made chips on many molds, including house molds. They are quite common and still used. If you want to learn a lot more about chip molds, go to Robert Eisenstadt's excellent site:

http://www.antiquegamblingchips.com/molddesignindex_site.htm

I hope this was helpful.

Michael Siskin