I had a 1978 KE100. It was my very first ride ever (beside the Honda 79 PA50 if that counts at all). My Dad would ride it to work as a commuter and loved to work on it, well when things went well. It was the first bike I ever saw the motor removed from the bike torn down and reassembled. I remember he done it all on a Sunday, it was early summer late spring and the wind was blowing through the garage and he laid the piston on the book to keep the pages from blowing around and he used a drill and was putting the crosshatch back in the jug. He got it together and got it running tweaked the carb a minute and handed it off to me told me to go test ride it. I came back and he asked me what I thought of it. I remember saying thought it was running really good and thought he should go ride it and he told me "nah it was not mine no more." I remember being confused what he meant and him explaining to me that he wanted me to have it and my watching him work on it proved to him I would have something invested in it. I rode it until I turned 17, someone stole it while I was in boot camp, and it was recovered to never run again.
Anyway they parts can be had at any Kawi stealership they made them for several years and like afore mentioned as well as can be sourced Ron Ayers, Mr Cycle, Ebay etc.