But there is a very strong possibility they are all from the same place even though monograms are not exact. Happened a lot in france, too... and even different monogram designs on both sides of the same piece isn't uncommon.

You can try searching CA for Mimizan, Casino Kursaal Amelie-les-Bains-Palaldr; Ault and Aulus. Also, a chip didn't have to run the duration of the house... especially after 1960... when it could have migrated anywhere -- and even prior.

It's mostly the postcards and metal jetons that tell the whole story in many cases.