Codger, You should try dealing with the US post office. There is no England or UK, but there is Great Britian.
I belive what you are describing is a "Kettering" system or saturated coil. Like old cars with points, but using a transtor trigger with a hall switch for a sensor instead of points
There several kits here for this type of system.
Pluses and minius for this type and for a CDI type.