Disc Brake Splash Shield Replating ?

They were originally galvanized. The metal was galvanized 1st and then the parts were stamped out of the galvanized sheet. There is no way to re-galvanize them. Your picture looks like they are in decent shape. I would just soak them in EvapoRust for about 20 minutes. That will clean them and brighten the galvanizing. If you leave them in too long, EvapoRust will remove the galvanizing. You can clear coat them with a satin clear after the EvapoRust bath.