M1 Helmet possibly WWII/Korea?

[WWIIBUFF]

This one also from an antique mall and the surface isn't as tough as it is with the previous one which has a sand finish and may be cork but could just be worn down some. It doesn't appear to have a heat stamp number as I dont see one anywhere on the helmet. Could this one be WWII/Korea era or is it 60's-80's?
Thanks
John

[earlymb]

Looks like typical 1960's, but there should be a number stamped in the shell that will give some more info

[Sleepwalker]

Hello.

could you check if you can find a marker in the shell?

This color was used from around 1965 until production ended in 1977.

The liner is a pattern from 1964. Produced until 1972.

Regards.