One way to check an old photograph is to research the City Registers for the town or in your case towns, listed on the front or back of old photographs.
These were published yearly and will have the business address for the photogrpher listed, which usually corresponds with the label on the photograph.
This will give you an idea of when the photographer was in business. Kind of helps you get to the "Ca." piece of identification.
However, my take is post-war. Still a neat photograph.