Heres a real easy make shift head brace.
There was an old microphone stand left in the unit by the previous tenants, so I bought a cheap microphone clip off Feepay.
It was a little bit tight but with a little hot water and bit of bending with a hairdryer… okay its not period specific/accurate but then again, so what?
It fits snuggly with a tinybit of flex for the sitters head to sit into. Its about 5 inches wide.
I thought I was doing really well with this, then managed to lock my keys in the studio, so have to pop back sometime with an angle grinder and a very long extension lead. Dopey old so and so.