I don't know if this has been mentioned here before...but I was just watching ESB and while I'm not a Boba, I pay attention to the man whenever I see the movie. 8)
I happened to look at the boots, and something rang a bell...so I went and looked at the MoM pictures, and yeah...those really look like a vintage pair of cold-water HAT diver's boots. My uncle did HAT diving and welding in the late 70s early 80s, and he had a few pair of boots just like these, but without the piping, which appears to be glued on.
Just for the sake of passing along info, if you're wanting a good pair of base boots to build up, look for some SCUBA boots. XS Scuba makes a decent pair, but they're all round-toed.
Again, don't know if this had been covered, I did a search and didn't really find anything.