I'm not sure I can help you, but you might try Stan Nycz. I don't know if he is still around or not. I believe he was not in the best of health a couple of years ago. (it was Gord McArthur who told me about Stan. Alas, Gord is now gone; a good man.
)
Here is some contact info I found online:
Stan Nycz has operated his camera repair and exchange business in the west end of Toronto for many years. In that time he has repaired many of the mechanical cameras of the thirties, forties, and fifties. He can be reached at International Camera, 816 The Queensway, Etobicoke, ON M8Z 1N5, telephone (416) 255-3072.
Let us know if this works out for you. I've been meaning to look him up myself.
Cheers,