In the early 80's, we made a lot of parts from Phenolic material, which can be had in many different formulations, depending on what you want to do with it. It is non-metalic but machinable.
this is a good explanation site.
I specifically remember using a lot of the light green and tan material, and we made rocket guidance housings and gimble blocks out of it.
"If you can find a path with no obstacles, it probably doesn't lead anywhere." -- Frank A. Clark