It's one of the Touch and Sews in the 600 series, 626 or 636, post 1960... (mid- 60s), not really collectable or highly desired, but some people like them. There are a CABOODLE of them out there-- you see them everywhere. $20 is about the going rate for one of these and you will see it again for that price, or less, and often.
Don't waste a lot of gas to get to it.