Steve Belanger at Mainly Magnetos said : We don’t work on them anymore
He advised Jack Kirkland at Automotive Electric in Michigan, 500amp@gmail.com : He says "Have no repair parts in stock for the generators used
on Douglas"
Steve Belanger also advised Kurt at Auto Electric Services in New Hampshire. 603-642-5990.
Did not called him.
All 3 of them are in the USA.
Hope this helps.