barracuda grille

On the grille for my 68 barracuda the studs holding the trim on it are spinning when I try to take to nuts off. The studs and nuts are very rusty, I have tried to hold the stud with vise grips and turn the nut with a wrench and this resulted in the stud breaking, several were already broken. The chrome is not in good shape, where can I find a new trip piece, I looked on year one and they dont carry one for my car. Can anyone help?

Evan