Printed circuit pins repair

CLEAN them best you can. Fortunately, copper is soft and easy to clean

BUY some solder that is specified for electrical / radio / TV work. Radio Shack solder isn't that bad

Also you might go to your local welding store and see if they have a product called "No Corrode". Not sure of the spelling I was unable to Google it. It is a pink past flux, used to be in a tin can. Make CERTAIN if you but a separate flux, it s safe for electrical, and not acidic