Im going to try to use those green foam blocks called wet foam. Its that crumbly green stuff found holding up fake flower arrangments.
Its very cheap and found at walmart, it takes shape even via a finger poke. So it should be easy to form into guantlets and to make a negative out of.
I also picked up some foam cones, to make the rocket out of, all cost me about 10 bucks at walmart in the fabric section.