The Russian GSh-6A pressurized helmet for high altitude flights. This helmet was usually used on MIG-21, MIG-23 and MIG-25 fighter/interceptor airplanes. The clear pressure visor is electrically heated to prevent fogging of the visor. The introduction of this helmet happened in around 1968. Phased-out samples of this helmet were obtained after German reunification in 1991 from the former East-German Luftwaffe.....
.....And then became available to buy online and double-up as a very convincing space helmet requiring little or no modification.
Test Pilota Perxa (1978)
Last Flight (2011)
The Darkest of the Hillside Thickets - 20 Minutes of Oxygen Video (2011)
Red Dwarf S10 Episode 4 - Entangled (2012)
......And many others, which you are free to update me on or remind me off at your leisure.
(Tim, which ones have I missed?)