Fine press. Not a thing funtionally wrong w/ it.
Disassemble the whole things (a couple of bolts/circlips, etc) and soak in strong tea for a week as suggested for gentle de-rusting. (Let the tea stay at room temp or better.) Better yet, you can also go the classic molasses route so it doesn't discolor the surface metal.
is go get some "EvapoRust" which the best I've ever seen for leaving spotlessly-clean/pristine metal. (I use it on everything.)
I recommend discarding the primer arm/setup just on general principles. (I'd do this in even a brand new press). Use a separate [Lee] Hand Autoprimer thereafter. It's just as fast and gives you better feel.
I wouldn't repaint anything.
Wear`n Tear is like a man's face.
It tells a story.