Glued_FIngers

Does anyone know who made the drum brakes they used before 75? They were GIANT 4" brakes weren't they? I saw them on a old cup car in a field that had been turned into a dirttrack car. Who made them? I know Hurst Airheart made the big 4 piston brakes they used for a long time into the 80s and early 90s. But I am trying to find a set of those drums for a vintage road race build