If you like chips from Portland Card Co. (Square-in-Circle mold), you might like this old catalog from their Distributor in Portland. Has a business card from the salesman. Cover is hand dated as 1948. I've only showed 5 pages but there are 16 pages total in this 8 1/2 x 4 catalog.

JMB posted that Robin Specialties originally owned the SQINCIR mold and it was later sold to Portland Card Co. I don't believe Portland Card manufactured any chips themselves but had them made in Maine by Burt or ASM.

The catalog is yours for $15 delivered in USA.