I thought that too when I first found it, but upon closer inspection I really think it's a "K" not an "E". Maybe I can clean out some of those specks in there to make it clearer.
I agree. It looks like the L was struck over the K. On my way to my first duty station in Germany, I left my dog tags in the barracks in Frankfort. Didn't realize it until I was on the bus to Wurzburg. I had to make my next set on what looked like a heavy duty typewriter in Nurnberg. We used the dog tags on keys all the time.