There are some good pics in the "Art of...." books. I know one could be built out of a Sten Gun.
I'll try to skim through and scan the pics in the next day or two.
I skimmed through the books and the only pictures I found where the ones posted on the BBC page. The only other one was this sketch of Chewie with the Sten Gun based blaster:
The action figures might be a good base.
Will doBring it to life!