Strap does not belong on that helmet and the liner is a 57, it should not be in a 62 helmet.
He restores helmets, so is this a restore labeled as original? The dealer is helmets of war by the way.
He says the liner size is due to late war availability.
I just read DougB post on the dealer, and I will pass on him and his items.
The liner is a piece of crap. The way it bunches at the bottom of the photo just shows that an idiot put it on the metal liner band. This is just my opinion ( I do not have the helmet in hand ) The leather appears to be a light weight, 1 ounce, oak tan cow hide from the way it lays and hangs. Liners for combat helmets were made from sheep and pig skin that also have their own characteristics as a leather. My personal feeling is that this helmet is a clever restoration.
"Always do sober what you said you'd do drunk. That will teach you to keep your mouth shut." Ernest Hemingway