I have a feeling they stopped making spares, I have heard that the engine was made in canada, and that it may be possible to get new coild from their, but i have had no luck with that myself.
I will have a ring around, and see if i cant hlep you out with more info on the ings, and perhaps the 2-coil idea.
Or maybe see if I cant help you fiond a working 2nd hand coil.