Morning everyone,
ascertained that the problems with the surplus sellers you report are true, and that the cover has nothing to do with the helmet; this example of civil protection is in fair condition and within a collection of Swiss helmets is still an interesting object.
I have, for a long time, a mint example that I show you for comparison.

Regards
Roberto

Swiss m18/63 civil defence helmetSwiss m18/63 civil defence helmetSwiss m18/63 civil defence helmetSwiss m18/63 civil defence helmetSwiss m18/63 civil defence helmet