Ring boxes are cool.. When I was doing research for my project with the help of the internet [and others] it is/was sometimes possible that if the companies were still in business that they could look in their archives [if survived]. It was all very interesting.
I would try and get as much information as possible. You got to start out slow. Just can't start with 'Hey did you make SS rings for the Nazis?' A question like that would 99% of the time end the interview right there!! I had to ease in to it,,very slowly, tactfully etc. I got some amazing answers!!, Some said they did not make 'Mens rings',,just fobs cufflinks, tie clips. Some said they made nothing with political themes,that the bigger jewelers/manufacturers would only early on make military themed rings out of silver/gold. Most of the time they would cover their asses and many of course had their records destroyed by bombs, the war etc....