Mike, your question was answered in the thread, post #15. You need a lighted flywheel.
However, you have the correct engine, flywheel, starter, spacers, crank...
In your quest for an alternator, you may find lighted flywheel. If it was my project, I would find the charging coil (alternator) and install it.
If it won't charge the battery, I would use a trickle charger until the correct flywheel showed up.