Father's day Gift-WW2 Canadian Helmet

[Garry Shipton (RIP)]

I was doing my usual Father's Day chores(trimming the rear hedge-mowing the lawn).Anyway,my neighbor Bill was cleaning out the crawlspace under his back door.Catches my attention,& asks & I quote,"Do you want this or it goes in the garbage"If I had more than 4 Molson Dry's(Beer brand for you Auzzies) I wud have pi__ed me pants.WW2 helmet plus the original Khaki chin strap plus an 8 point helmet liner with a rubberish feeling liner.The problem is,the top helmet screw holding the liner to the helmet is missing!!Also,can't find any helmet Manufaturer's marks!!Any suggestions/advice form helmet guys for restoring the top center pin??