Getting one from H&L would probably be easiest and cheapest. The drawings for the custom tiller that came with my manual were a bit confusing- a big black X and comments like wrong curve do not use, revisions to follow- so, not knowing about H&L, I took some measurements and built a jig and made my own out of epoxied strips of mahogany and ash. It has enough curve to clear my kneecaps and thighs when I'm seated but is low enough that I can straddle it standing without having to worry about risking serious injury or singing soprano. It also rests at a very comfortable height for steering for extended periods and is substantial. Will take a pic and send it if desired. I still have the jig around somewhere so if for some reason H&L doesn't work out let me know and I can either make another or show you how. It's not that hard.

Tom
Furthur #332