This Keyboardstand ist designed with a minimal aesthetic in mind. It fits my MX Mechanical perfectly and will probably fit other keyboards <75%. It should fit bigger ones too, but i think for that it would need a longer middle part.
Assembly is quite simple. Just connect the middle part with the two sides, by pushing them together. Pin 1 in “hole” 1 and the triangle fits in the arch on the bottom. If you want to make sure they don't come apart, glue them.
I designed it, so you can also take it apart again.