Had a look at the liner and it has the third marking in your examples; (CA AC in a cross pattern). I decided to take a quick shot at the steel helmet with soft stripper, and there is a really good proper green underneath that still retains the proper "sand" finish; I also removed the major insignia( it was a pin that was bent over through the holes) and found a third hole (see photo); maybe the major pin was added? If so, what would have been on original, as there are 2 holes directly vertical of each other;
I will strip the steel helmet to the original paint, and post some other pics. I know it was repainted as if you look close, you can see some scrapes, etc that removed the "sand" paint, that were the same color as the helmet, hence being repainted over.
I guess I did all right for my $25.