yea i know what your talkin about. Had a clone many moons ago lol
The stuff that would need to be used is Foam-it from smooth-on. Its pretty ridgid but its super super light. It yeilds excellent detail as well if your casting it from a good mold. My wife had a jawa blaster cast out of this stuff cast from a real Ensfield rifle converted to a Jawa blaster. It was seriously like 6oz or something crazy like that. Plus it wasnt floppy at all. It was made with kids in mind which is why he made them that way. Alot of folks have kids that have Jawa costumes, so you would want them to have a light and safe blaster.
lol yea Dom..they seem to think we are all going to get into a fight and beat each other with out rubber weapons lol I personally wouldnt wanna get beat up with a hyperfirm E-11 though...ouch! lol