I have an alternate view of rust. I detest it, and it is my mortal enemy. Remember, it’s not just a coating. It is a parasite that is slowly eating your toy. It will destroy it ever so slowly and look for other hosts to attach itself to. It should be our sworn duty as keepers of these ancient toys to destroy the enemy.
I like Dave’s idea to restore just the fence. EvapoRust is your friend. Also, is the screw original? Make sure it is compatible with the metal. Corrosion and rust are best friends. Incompatible metals start corrosion.
George