Oh it's a vintage GE alright.
Near BOL but without a closeup, hard to tell what it has. I'd guess the year to be 1970 because of the style of panel. The knob in the middle is probably for water level, and it could even have a mini-basket. I remember the brochure from that year and they had a whole line of models with the tall lit backsplash, the medium backsplash and then the low BOL style backsplash with both Heavy Duty 18, and Heavy Duty 16(small) capacity machines. They were all over the place. Ask the owner to give you a close-up of the panel and ask questions about the machine. Even though I'm a GE fan, $50 is steep for this model, unless it's one you covet.