Your hub and drum looks to be earlier than 1952.
I agree. I just had one of my front hubs off to replace a seal and repack the bearings and they are definitely different than your picture. The drum on '51 and later (Bendix brakes) attaches on the outside of the hub, but it appears that your brake drums are attached inside of the hub flange.
I like Jerry's suggestion. Toyota copied quite a bit of GM's parts, including the 235 engine (with some slight variations.)