I just bought a couple of helmets from ebay. One is a m40 quist and the other is a hkp m42. How can I tell if the actual shells are fakes? The m42 is marked in the rear with hkp64 and under that is the number 3428 with the 28 very stamped very lightly. The m40 has a Q66 on the left side the Q is poorly stamped and almost looks like a C. The back has the number 11388 with the 88 stamped lighter than the rest. Now I paid $135 for the m42 and $96 for the m40. I know they don't have original paint or are authentic but I did want an original shell to restore. Can anyone help?

Thanks

Luke