I've seen those in the farmer's and handymen's tool boxes during the 1940s,

here are a few more.thx

close up

Usually there is a maker's mark or initials stamped into it somewhere. The abbreviations can be very tiny, you may have to clean the brass to detect it.
Casey

thx mongrel - I will check

I looked in the book Tool Collector's Guide and some of those types of rules have the company name somewhere on the rule section and not the swivel.

Of course, it's possible the stamped mark is under the bandaged area.
Casey