Here is the late 50's - early 60's soup can version by Trico these should be readily available at a wrecking yard and would seem to be an easy install.
https://www.flickr.com/photos/advance-design_parts_co/14177411581/in/set-72157631868452754
https://www.flickr.com/photos/advance-design_parts_co/14178067752/in/set-72157631868452754
Here is a dealer installed powered alternative in 6 or 12-volt versions to solve the issue, the label on the box describes it perfectly. This unit carries GMC (1937-53) Master Parts Manual reference and part numbers.
https://www.flickr.com/photos/advance-design_parts_co/11597350134/in/set-72157631868452754

1950 Chevrolet 3/4-Ton 3600
More pictures on Flickr