I purchased a Pertronix Ignitor (p/n 2846, $90) from Retro Rockets for my Bosch VJU4BL33 B18 distributor. http://www.vintageperformance.com/retrorockets/
We also had to file it a bit to get it to fit properly, like someone else mentioned, I remember.
If you have your distributor p/n you can look up the correct Ignitor electronic ignition system to buy at: www.pertronix.com
Another thing that I remember was the distributor gear had actually sheared off so I had to find another one. Be sure to check for cracks/fatigue when you have the distributor out, as I guess this is pretty common?


Regarding your alternator conversion: I originally bought my car from someone who had already installed a very cheap alternator in it - I think it was like a $35 alternator. Anyway, the alternator never worked correctly with the voltage regulator it had (maybe the voltage regulator was the one that originally worked with the generator? I don't know) Anyway, the moral of this story is, we fiddled around with this combination of alternator & voltage regulator for quite awhile - draining the battery every night, recharging the battery the next day - something wasn't working correctly, I don't know if it was the wrong voltage regulator for that alternator or what. I had the alternator replaced with a new one of the same kind, and my "system" still didn't work - it just couldn't charge the battery. Finally I took my car in to a "real mechanic" (the Swede) who concluded that the whole combination was just futile. He installed a 61A Bosch alternator with an internal voltage regulator in it that he said was "bomb proof." I have never been stranded since. Since then, I've always thought alternators were quite complicated - and that the conversion is a black art. I guess I don't know how one goes about picking an alternator. :)