Wehrmacht cap

[Thodoras]

Can you please give me your opinion for the cap? Thanks a lot Ted

[ErWeSa]

Another Falschmeister, see here: Luftwaffe M43 opinions

[Aldo]

Wow, great advertising

[ErWeSa]

I wish all producers of repro caps/fake caps would mark them likewise - it would ease our lives a lot.

[Thodoras]

thanks a lot for your input

[Kohima]

Sadly, not a guaranteed fail safe for those lacking in familiarity with the German language... and not beyond defacing by an unscrupulous seller.
Without that stamp, this is a very convincing copy (at a distant first glance), probably made from original cloth.

I think the only sure way would be to use an entirely inappropriate panel of fabric for the lining (perhaps the top section), which would require a major rebuild to replace and, thus, leave evidence of tampering.
Such a piece would still be good for display or re-enactment, without the danger of fooling too many people.
Ah, if only we could pass a law...