I remember seeing Warby's Jet-Boat soon after the world record run. It was a big event and put Tumut/Blowering Dam in the world spotlight. From memory the jet engine was supplied from a RAAF Neptune. There was also a story afterwards that his return run "could" have been even faster if some "hooligans" hadn't upset the dam swell with their outboard motorboats.
Due to the drought, Blowering dam is now only at 30% capacity.