Sheet Metal for 1966 Plymouth Valiant 100

It depends on how bad they are those pieces aren't available for replacement something you're going to have to find used or rebuild the pieces you have with new sheet metal
I'm not sure if this is a common problem with these cars or if it's unique to my specific car, but halfway down the fender on the top next to the fender/hood gap there was a small patch (about the size of a half dollar) that almost looks like water had collected there? It's hard for me to explain from memory but I was told that the best thing to do would be to replace the fenders. Any thoughts?