Re: M84 scopes manufacturers
April 1945 is most frequently given as the date the M84 first came into service.
There's a very brief article on the Fulton Armory site by Bruce Jackson about M84.
To save you the bother of reading it yourself, the key info it gives is:
<span style="font-style: italic">"Peter Senich provided the most detailed information on these scopes that I have found in his book LIMITED WAR SNIPING, Paladin Press, 1977."</span>
and:
<span style="font-style: italic">"An additional source of information on the M1D/M84 is the book, THE LONG RANGE WAR: SNIPING IN VIETNAM by Peter Senich, 1994. In chapter 1 he goes into some detail on the build up of U.S. military activity in the 60's and their reliance on the M1D. Very detailed information with excellent black and white photo's showing details of the various rifle/scope combinations in development are included.. As to the number of M84 scopes produced, the only hint I could locate was in a photo credit Senich gives on page 19, "....with a total of well over 40,000 M84 telescopic sights manufactured before production finally ended, and with the U.S. policy of "surplus disposal" such as it is, this 2.2 power scope will undoubtedly remain in service someplace on this globe for years to come." </span>
In the absence of anyone here having details on Libby-Owens-Ford annual production by serial number/by year, looks like tracking down these books could be a good place to start?