Timing Belt for an Old Janome machine

Question

I am looking for a timing belt for a 1974 Janome free arm machine. It's light blue in color, the front of the machine says 'American Home'. The back side says made for Dial and Sew by Janome. Model FA 772. I have called several companies, even the Janome. They said it was a generic machine that had several different name plates put on the front, and the belts were no longer available. Could you help me ? Thank you !!