It seems to me that even if available, by the time you buy a starter, flywheel, and charging coils, and add a battery, you have added weight, cost and complexity to the bike. Why not just use a kick start? These motors fire up so easily, I would think they would start on the first kick 90% of the time.I guess I don't have a great answer and you are correct that a kick starter is the obvious answer. My wife will probably end up riding this and I'd like to make it as easy as possible for her to enjoy. In addition, I like solving technical problems and helping folks. Even if I go with a kick start the information on if this is even possible will be available.
As far as a battery goes I was thinking about the newer lithium polymer batteries. I have one the size of an Iphone that will jump start my 4 cylinder car. It's pretty amazing. with something like that, the weight addition would be less. The net gain would be the weight of the starter and coils and should be around 5 or 6 pounds.
The battery looks like this...