I hasten to say that I'm not going to buy one, but having seemingly fried mine when the cut-out points stuck "in" last week, I was looking around on the web and found this. http://www.woodauto.com/Component.aspx?Ref=WG35
Is it a direct replacement (of course including installing the included regulator)?
Woodauto rebuilt my dynamo with a new armature and field coils about a year ago. I found their service to be excellent. I spoke to them on the 'phone a couple of times and they couln't have been more helpful.