From ESPO: Give them a call.
70-74 Barracuda, Challenger (E-body) - $220-$250/pair
63-76 Barracuda, Dart, Duster, Valiant etc. (A-body) $220-$250/pair
66-73 Belvedere, Charger, Satellite, etc. (B-body) $210-$250/pair
66-73 Chrysler, Dodge Full-size $310-$400/pair