first of all how dare you
no, seriously, actual ruskie reporting in - the Пилотка is specifically a female infantry hat - it'll look handicapped on you if you don't wear the matching Soviet army uniform.
and even then it's kind of a
women's hat, like what the "fedora" (actually a trilby) used to be, so it'll look handicapped on you anyway.
we don't need nice guys killing more than one type of hat.
also, the GP5 gas mask plad posted isn't even very effective - most old gas masks are faulty (zero percent protection) and don't really guard your lungs against modern "gas".
sure if you get a good filter you can fare well in areas with nuclear, biological or riot agents but the mask itself is made from latex older than the British queen and will do forget all against ammonia or blister packs or other corrosive murder-stuff.