Al Rollins once told me the name back when I was buying chips coming over from Cuba that weren't actually casino chips, but rather simply gambling chips... It had to do with private operations; the term (if I remember correctly) started with 'ap' and ended with an 'o' and it was only members of these groups who would gamble there. The examples I had weren't too popular with Americans (kind of crude stampings; numerals/letters and combinations of both; both new manufacture and overstamps on common C&S chips) because they were not actually casino chips... but the collectors (per Al) in Puerto Rico were very interested. I think Al also told me that these "clubs/operations" were in Puerto Rico as well.