Rust! Should I sell it?

To me it really depends on how the seams are.

If there is rust pushing out the seams that's a problem

My rescue 67 dart convert has a few bad areas but all in all it's pretty solid.
Pass side top opening

Up under the pass side top opening


Pass side forward most seat mount rib


Pass side floor board

Behind rear most inner drivers side seat mount

Driver's side floor board



The metal is solid enough overall I can stand on it