I'm not sure I would go or one of those you describe.
Try for a Bernina Nova 900. There is one on ebay for $51.00 It is a great machine and very portable and Bernina quality, and in demand now. They no longer make these. There is also a small Kenmore made in the mid 70s that is also a good machine and portable.
Also, is there a dealer in your area who sells used machines.
If so, give a call and tell them what you are looking for.