After 2nd world war the M35 helmet model has been manufactered again as the Stahlhelm M35/53.
The pictures below show a model used by the BGS "BundesGrenzSchutz"
This is the helmet with vent holes
The picture below shws LS 64. Size 64
LS stands for the manufacturer Linnemann & Schnetzer,
It seems that they do not make any helmets anymore.
Read about the BundesGrenzSchutz or BGS
or read about GBS history: https://www.nadir.org/nadir/archiv/Antirassismus/bgs_broschuere/t21a.html
See a video bundesgrenzschutz video