I have a friend who is a physical monster; does Turkish Get Ups easily with an 85 pound kettlebell. He built a suburito from a length of one inch steel rod. He did something to elongate the tsuka in cross section and then wrapped it with parachute cord. I haven't weighed it, but it seems to weigh four or five pounds. Not my cup of tea, but it certainly met his needs for something heavier than was available.
Has anyone read the novel Snow Crash
? This sounds a lot like the "redneck katana" mentioned therein.