Hello, I'm hoping you can help me identify this EGA. I found it in my dad's EGA collection. There is a very faint GEMSCO NY stamp and when I use a silver cloth it shines up nicely, but there doesn't seem to be a silver hallmark. It measures 1.5" from top of the eagle's head to the bottom of the anchor. I've researched online as well as referred to my copies of "Equipping the Corps Vol. 1" and the "Eagle, Globe & Anchor 1868-1968" and unable to confirm the type of EGA. Any insight would be appreciated. 

Could be a nickel plated. Looks like you can faintly see gold gilt under it. It’s a M1937 WW2 Enlisted cover emblem. Nice pierced anchor hallmarked variation. 

Thank you @stucky151 your insight is much appreciated.

Post-WWII, possibly pre-Korea. This is when Gemsco started producing marked enlisted EGAs, and this one is marked in the crossbar