I just bought a 401A freshly serviced (oiled, greased, tension checked etc.) with original 5 cams, other attachments and manual for $50. It's in excellent condition and I'm very happy with it.
I'm looking at a 301 long-bed from the same seller for $100-$125. She's doing the service now and couldn't give me a firm price.
I know if you get on e-Bay they sometimes just take right off.
Good luck! They look like lovely machines. I'm surprised you can bear to part with them!