Initially I would check if the coil has continuity, also does it leak to earth,
I am assuming it shouldn't,
Do you have a multi meter?
Good news is that the bike is a runner,
Does it also charge the battery??
If it does work, leave it alone,
Use the bike, but you could plan ahead with trying to source spares or other ignition/generator system,
Like Electrix world, etc
Gist is, if it works, good,
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