Dave801,
I am in the process of restoring an original OD-C1B for my October 28 Leatherback. They are hard to find since these were only used a short time. If yours is like mine the shagft which drives the blade is not in the center of the unit. I purchased mine from Berts. It was an original untested unit. You might contact them to see if they have any more. There is also a supplier on the web "Model A Wipers" who sells rebuilt units outright. They are not cheap but I think they come complete and rebuilt. At this point I think I would have made out better if I had paid the price. If you need any photos let me know. Look at the Model A wipers site since they have sketches of the various versions. Good luck.
Supergnat