Driver side door hinge bent

A jackass ran his bike into my opened driver side door. Anyways I need to replace at least the upper hinge now. I think it is just bolted on but I havent looked that close yet? Anyways any advice would be helpful.

I bought a used pair of hinges from the junkyard today. Anyone know how to clean them up. Im not sure what to use to get rid of dirt and rust on them.
Thanks