I was going through several 91/30s I had bought about 15 years ago. All are "refurbs". I recall at the time I bought them I had been told a 1942 Iz. had an "East German" marking on the receiver. If this was even true could someone help me on what the marking was? Also second question, has the debate been settled on what the marking "MO" means on one of these? (if anything). Thanks for help to anyone that replies.