Call Ralph and tell him you want two #5469245 rear wheel cylnders.
Used on 67-75 Camaro-Nova & Monte.C/Elcamino/Chevelles also.
(but NOT St.Wagons)...tell him to look on Pontiac Firebird/Tempest/Grand Prix-Olds Cutlass & Buick Skylarks too.
http://www.classicmusclecarparts.net