Please forgive me if I'm posting in the wrong forum. I'm not an engineer, but love to fix things. I have this 6 volt AC regulator off a vintage 2 stroke that I've restored for my grandson. Only thing left are the lighting and charging circuits. I unpotted this regulator as I knew it was bad (pics attached). It's a part that is NLA. Very simple design, as it seems. As near as I can tell, these are old tunnel type diodes, but can anyone here help or confirm? It would be greatly appreciated, and thanks for being patient with a newbie like me. It regulates the AC voltage from the magneto that then powers the 6v AC headlamp. Then there is a small rectifier in another circuit for charging 6v DC battery and powering the turn signals, horn, and tail lamp. Thanks again!

 

I'd also welcome input on how to recreate this regulator, hopefully using more modern diodes if practical.

 

As I continue to study the service diagrams, is it safe to assume I could just use Zener Diodes to limit voltage based on the attached diagrams?