I used an old 1/6th vinyl model kit from Kaiyodo from the mid 1990s. The head can turn and the arm is moveable at the shoulder. Since it's hollow I've added an elbow joint from an old 1/6th figure I had lying around. It means I can now bend the right arm more than with the standard kit elbow would allow.
I've finished this up today (except for Chewie's blaster, waiting on an ESB one to arrive). The scenes during the Bespin escape a re a complete mish mash; sometimes there are two right hands, sometimes a right and a left, sometimes the left shin is in the left thigh, sometimes it's in the right. The same goes for the loose arm on the other side. This is what I ended up doing...