Glad to hear things are looking up for your FA50, you should be good for many miled of riding now.
The ignition and key is hard to find unless you feel like paying $35 to Bikebandits.com, I don't even have one for me.
Regarding the hard start problem, try adjusting the mixture screw.
Adjust it so it starts easy, run it and shut it down over night.
Next day do it all over again.
I had the same problem and the adjustment helps.
I just bought a FZ50 engine case and internal parts.
It's a 2.5 HP with a 2 speed auto trans which I hope to transplant into my FA50 frame.