I’m thinking about to make an open source project oriented to newbies, with simple materials (maybe cardboard), with instructions to produce all the parts and share all the files. I’m making some tests… https://www.youtube.com/watch?v=c-tJj0PCT-8
Be it cardboard, plastics etc, you can buy them easily enough. The beauty of your constructions is that, regardless of material, you can transfer/attach your designs to the material and cut them out, then construct them. As someone who is way more comfortable with the programming of projects this is simply brilliant.
I’ve ordered 4 x SG90 micro servos to start tinkering with limbs and suchlike, so may have to replicate an arm or leg of one of yours