All the suppliers sell them, but do any sell pads that stay on?
For the prewar and deco trucks, many were designed for use without rubber. If your pedals are in rough shape, they pop up on fee bay all the time.
I am using a set of big truck pedals for my 1940. The big trucks used a frame mounted master cylinder. The pedals still bolt to the bellhousing, but the master cylinder is bolted to the frame. I figured this would be easier to manipulate when I install the new MC for the disc brakes. It gives me plenty of clearance for my transmission.