A friend of mine didn't care for original Squats, so he took some plastic Space Marines and chopped the legs and torso a bit. Can't give blow-by-blow instructions, but they didn't look half bad, especially adding some squat heads for guys with the helmet off.
Add some rivets and tubes, and tart up a large, plastic bead for the helmet, and you might have something worth the effort.
Otherwise, I'm tapped out.
Doug