4 1/2" bolt pattern rotors

Hey i was wondering wat i should do..i have a 70 duster with disc brakes on it with a 4" bolt pattern..a buddy got me welds that have 4 1/2" bolt pattern and i was wondering if there they make rotors for that year with the 4 1/2 or if theres another yr car rotors that will fit?? :read2: