cal-sportbike.com is the only US distributor. Currently, they are on a 8-10 day backorder, but they won't charge your credit card until they ship.
SpeedoHealer is easy to install. If you have basic mechanical skills it shouldn't be a problem.
Installed the speedohealer on my bike Friday night. Nice product, easy to install,
perfect correction of my speedo. No more reading 12mph faster than actual speed!!!!
My bike has different chain/sprockets installed and the prior owner never corrected the speedometer. The speedohealer ties into your factory harness, and allows you to correct the display. I took my bike up to 60mph actual, determined by my Garmin GPS, then noted my speedometer, it read 72mph!!!
I followed the correction formula in the speedohealer instructions and entered the corretion factor into the unit of -16.6%. Perfect!!