I'm no expert on these but my WW2 M33 has a leather chin strap.
I'm sure an expert will chime in soon.
canvas chinstrap ,post war im afraid morris
The large cloth chinstrap, metal liner eyelets and the trapezoid shaped hangers indicate a post-war issued helmet. The Italians used the M33 until 1989. Not worth a high bid, for sure.
"Much that once was, is lost. For none now live who remember it."