Well, at least I seem to have done something good (grin)! After preaching the fear of the Lord into the seller in the forum where he was (before he put it up for sale) informed that this helmet is not alright, I noticed that he did not only remove his thread there (grin), but he also changed his description on eBay into something more truthful.
It's sad though that there are "collectors" who first ask "What do you think about this?", subsequently are informed that the helmet is cobbled together from mismatched and contradictory parts, and then still put it on eBay as a completely genuine, totally original, and extremely rare helmet.
Anyway, so many people became pissed off at him in the other forum, that he changed the part "(...) it is complete and incredibly rare, as of now the only one on Ebay (...)" of his description as follows (I put the changes in bold type):
Up for sale is a World War 1 Ersatz Steel Pickelhaube Helmet. This pickelhaube would have been produced right before the M16 steel helmet. I have been told this is a Prussian pickelhaube due to the unit stamping on the shell, with the original front Baden plate and original Baden cockade added later on. The original chinstrap seems to be an M16 helmet chinstrap but original. The Baden cockade is loose due to chinstrap end, probably can be pressed in with a little force. Everything else is secure. I have been told BIA VII is for "Bekleidungs Instandsetzung Amt VII" and G for "Garnisonsdienstbrauchbar". Stamping on the lining appears to say "Albert Schaab Kreuz---- I.W."
I'm happy to see that even newcomers to the enchanting world of Pickelhaubes now have sufficient information to understand that what's offered is, in the immortal words of 911car: "Wrong plate, wrong cockades, wrong chinstrap... what is left??.. a rusted tin shell".