The front and rear wheel cylinders have different bore, therefore different part numbers.
Here's what I found:

My application: B-Body 1969 A12 Superbee with HD suspension package (11"x3" Drum Brakes Front & Rear - Factory)

Front Wheel Cylinders (Orielly Part #): WC40416 These have a 1-1/8" Bore
Rear Wheel Cylinders (Orielly Part #): WC78734 These have a 15/16" Bore

Front Drums: Bendix PDR0019. 11"x3". (Found New on Ebay)
Title: ==> Brake Drum-HEMI Front Bendix PDR0019


Rear Drums: (Found New on Ebay)

1965-1970 Chrysler with Heavy Duty / Police / Taxi 11 x 3 inch rear brakes

1965-1970 Dodge Fullsize Cars with Heavy Duty / Police / Taxi 11 x 3 inch rear brakes

1965-1970 Plymouth Fullsize Cars with Heavy Duty / Police / Taxi 11 x 3 inch rear brakes

Part #: BD 2923

Drum Inside Diameter: 11 inches

Fits Shoe Widths Of: 3 inches

Bolt Pattern: 5 x 4 1/2"