I know these are not really an Imperial era item but they pollute sooo many beautiful bars that we all love I felt this a good place to post. I don't know why but these have become a pet peeve of mine and I have passed on some really nice bars that were mounted in the mid 30's do to these. Having said all of that I must admit that I do LOVE the pin back ones. The odd pieces find a little spot in my heart. How many firms produced these? I know there were two with different dies. Anyone have