I went with the old saying "Why buy it, if you can try to build it?". So I did with the old Jiffy i bought last year. Turned the old one armed bandit into a more modern handle assembly. Just got it fitted tonight. Have to put a coat of paint on it, and figure out the throttle linkage. Can't wait to try it out, and hopefully no more almost busting my wrist. I should also mention that I have $0 invested in it. The black handle parts are an old push lawn mower handle assembly modified to the size I needed, the 3/4" bar for the handle to slide on I had in the shed, and the plate that bolts on the the gearbox was made at work on the plasma table with scraps that we had around.
Before
After
Got the rest of the mods finished on the Jiffy.
Gave the motor a quick refresh on the paint. Taped over the old decals so they are still there, would like to find some new ones. Got the handle assembly painted and bolted together. Made a throttle assembly out of a brake handle off of my old mountain bike, and a the throttle cable out of an old weed whacker that had taken a crap on me this year. I left the old throttle on there for the first few runs to make sure everything holds up.