Well, I took it back to the antique shop and explained my "buyer's remorse." Explained that I wasn't able to come up with any info. on internet with that model & s/n. Didn't want to have to purchase a manual (or be able to find one) and then the new belt. He was very good about giving me my money back. I couldn't leave without explaining all that I learned (here). Told him the Atlas case and pink foot pedal might bring him some money but wasn't so sure that machine would ever again bring him $50! He admitted he didn't know anything about sewing machines and appreciated my telling him all I had learned.
I also wrapped the foot pedal in plastic before taking it back to him and explained how placing an unprotected foot pedal on the bed of a machine could easily cause unsightly scratches.
Next time, I'll be sure that the label on a machine matches up with the brand label on the case!