For whatever it's worth I have an ejector 12ga marked F on the frame table & E on the bbls. It is a much higher SN than this one, of the single, large hook type #38025. The engraving on this one would appear to be F style for the era, as well as some other features. Bbls are Chain damascus. Back when I first acquired it I assumed the E was for the ejectors, but have since learned this was not common practise.

Miller/TN
I Didn't Say Everything I Said, Yogi Berra