Did anyone see the combo set on ebay this last week - a made up B helmet and D mask? I think it went for £110 and wasn't shockingly bad, more an "it'll do" type affair.
Repros might seem steep but they are infinitely more affordable than the real thing - and they're going to be in much better condition because the wool always seems to be mothed. I don't know the origin of my repro, but it was an ebay buy-it-now for half the price of Seftons (no disrespect to him!)
Ultimately to choose to represent the earlier aircrew means financial outlay of some sort to pull it off properly. That's why in the wider sense you don't see converted Swedish tunics or '49 pattern BD in the reenacting hobby anymore.