I think the AVG helmet has the right shape (great find eagle eye!) but it looks like maybe it was used as the base then a layer was sculpted on top. Note the depression on the rear center ("reverse mowhawk"?) and that the brow plate depression (silver part with star bird emblem) continues onto the helmet from the visor. Where the visor is attached it also is sculpted/cut around that. Also there are the cuts out where there are some greeblies on the rear and right side as well as cut outs on the ears both sides. The brow plate appears to be riveted on, possibly a custom manufactured piece?? Even the lenses on the AVG helmet are roughly the same shape. I think that the Chinese helmet may have been the inspiration, but in my opinion isn't the "base helmet". But it's all guesses just like everyone else. I guess that's why we have these discussion and we'll eventually get there.
Jim M.