I suspect they may be Chevy passenger car hubs and brake drums, maybe 51-54 (same year range as Bendix brakes were used on the trucks). Per
this [
chevy.oldcarmanualproject.com], the bearings are the same for 1/2 ton and passenger cars. Passenger and 1/2 ton drums were the same diameter (11 inch) and shoes the same width (2 inch front and 1-3/4 rear) in that year range, and I believe the only difference would be 5 lug instead of 6 lug on the trucks.
Look for a casting number on the hubs, which might tell you what they're from. See the attached screenshot.
[on edit] the wheel lug pattern was 5 on 4-3/4. You might double check yours. With 5 lugs it's harder to measure.