I really like the pic of the symbol on the front of range finder ear. Looks like it was made from a vinyl lettering kit using D, V, and : Very cool pics thank you
Looks to me like a lot of the mark detail was done that way, it's either lettering from a model kit, you know, the stuff you have to soak in warm water and slide on or Letraset.
It still exists nowadays but it was a big thing when I was a kid (that's late 70s early 80s, yes, I'm a relic
) all you had to do was rub your pencil over the sheet and the letters would come off, the crack was though that if you didn't rub correctly they would only stick to whatever you were rubbing it on and the rest would stay on the tracing paper, leaving letters similar to the ones on the helmet.
The other thing was they could scratch off easily too.
The final thing was that the sheets had the specific letters in a row, so I could see it was entirely possible that the bottom half of the right ear could have a set of letraset I's rubbed onto it, as they were already neatly spaced. Then they could have been scratched off with a needle.
Check out
www.letraset.com, however I cannot tell the font used, possibly arial, but it's definitely sans serif.