That's what I was thinking, too. All but one of those parts can be easily milled from flat plate. The yoke end is a bit harder, but yoke ends are cheap standard parts and there's probably an off the shelf solution.
The ball joints they use are standard R/C car parts. Those are available in in a stronger form, nylon with a brass ball, for EUR 0.53.[1] It won't be hard to strengthen this design so it can do useful work.
[1] https://toni-clark-shop.com/Ball-Joint-for-M2-and-M3