Hi Filipe, I agree with your doubts about this one. The liner is not original, the chinstrap has issues, and the exterior anti reflective finish does not appear original.
As far as the Brodie style helmet, that one is a puzzler. I've never seen anything like it. Fascinating helmet. I had not previously seen this thread. I will move it over to the Polish section for a while in order to give it some exposure to Polish collectors. Let's hope we get some input.