The machine you are looking at is a Singer 201. The 201 is the top of the line singer from that time. I refurbish both 201's and 15-91's and use my grandmothers 201 for quilting. $75.00 is a very good price even if it needs a little cleaning up. $50.00 would be better but $75 is good. Be sure to check the wiring behind the motor to makes sure the insulation is intact and not cracking and coming off. In my experience the one's on craigslist that are in a cabinet are usually in pretty good condition. If the wire is bare and it touches the metal machine head the whole machine can become live. I rewire motors and it is not difficult to do if you like to do things like that. But I would take the 201 in a heartbeat.
Cindy