Hi Kara. The FW, as you probably know, was made in 1951 and as for the price, well, I think they always ask too much for those things just because they're cute. The attachments shouldn't be hard to find.
The second one is a model 15 with a vertical bobbin which makes it wonderful to do FMQ, especially since it is in a cabinet. Yes, the light and the motor were standard, and the potted motor of the model 15 is one of Singer's best. It drives the motor directly without a belt.
If you have the space, I would go for the 15 in a cabinet because they are woooonderful to sew on. OTOH, if you want to go to classes and need a portable one, the 221 is great for that. Me, personally, I'd hold out for a lower price though. But that's just me.
Good luck and let us know how it turns out.