Thanks. SAECO is a possibility as the manufacturer.
What you saw as CAC is actually CAL (California). The address was Pasadena 8, Cal. That was the old way of designating postal zones in large cities. (Edit - Vlad beat me to this one.)
I’m sure the last notation means From Tom Dunn. He was a very well know cartridge collector. One of the pioneers. If the cases came from his collection that would add a lot of weight as to the maker.
SAECO was a large shooting/reloading tool manufacturer, distributor and retailer in California after World War II. If John Moss is reading this he can tell you a lot more about them.
If SAECO did make the cases it would be a big help in dating them. But, I still don’t know what the hand written note on the box means. Any ideas?
Thanks again to all who responded to my question.