Hello nhbenz. Mystery solved! Thanks for the reply and the spot-on ID. I find many old bottle caps and always check them for something just like this. Too bad there was no bottle, only the broken neck was left.
Merry Christmas and prosperous new year to you. C9
nhbenz to the rescue again! I had searched quite a while the first time you posted this, and again for this thread and never had any luck at all. glad the mystery is solved