Help identifying these helmets, please?

[RelicHunter99]

Hey all, brand new to the hobby and have stumbled upon a guy in my hometown who owns some pretty amazing stuff, most of it well out of my league right now. But he has three helmets I'm a bit interested in, can anyone help me positively identify these? I'm primarily curious in the black one. It must have been painted at some point, but even the shape confuses me, it looks too tall to be an MkII.

[Walkwolf]

The black one is Civil Defense, Conservation Corps, or a miner's hat but it
should be white underneath the paint.

The other two are swivel bale US M1 lids, but not in the best shape.

The .45 holster should have a date on the back..............

[rra227]

M-1916 Bacon Can,maybe theater made knife. Rich A. in Pa.