The foregoing posters have said it all. So let me suggest that once you decide on a machine, you look st shopgoodwill.com and search for "sewing machine". Watch the shipping cost and don't bid on anything because you want the case (it has about a 50/50 shot at making it intact).
I'd primarily look for a 301A if I wanted to travel with a vintage machine. Though I wouldn't overlook a 158.xxxxx Kenmore. Plenty around, usually cheap, work well and offer a few utility stitches. Feet do not interchange with your 401.
I fell in the rabbit hole about 10 months ago and how have 33 machines... be careful!