Hello friends,
I plan a diorama about the revolution in Portugal 1974 (carnation – Revolution) I’m searching for steel helms in 1/35. Does anyone have an idea?

You would propably be looking for the french model 1951 helmet, this can be found in several of the old Heller figure kits. Many of these might be hard to find but Italeri have reissued some of them, look for the most recent one called "Allied Support Troops", while the box portray them as ww2 they are really french troops from the 1950/60.

Alternatly Hornet also makes a set of resin heads with this helmet, you can see it here:
http://www.greenwichgateway.com/hornetandwolf/Hornet/HEADSETS/PAGES/Hfh05.htm