Lube/unstick = 50/50 mix of acetone and ATF or PB Blaster.

Derust = Evaporust

Make them smooth and last another 50 years = disassemble and machine to straight smooth bores and a fresh, straight pin.

I'm looking into this for my van hinges, but the side and rear door hinge halves on the doors are riveted. I'll have to machine in place or disturb the rivets, which I'd prefer not to do...