I have everything - regulator, prop, mount for a J4 (gear looks a lot like the early Champ; I will check the bolt pattern). I am getting 25 starts per charge without the generator - with it installed I had to do a couple of fast downwinds to get it charged up enough for the next start. Generator puts out almost 15 volts at 90 mph, but is a bit sluggish at 60.
Happy to sell it to you, but it sounds like you need to sell the Champ and get a 7ECA with alternator and toe brakes. A superb airplane, and lots cheaper than converting the 7AC.