[chris vickery]

Brad, here's a suggestion for you.
I refurbed a couple of these lights a few years ago and ran into the same problem, the springs and cups being very rotted out.
I went to the auto parts store and found some small frostplugs which were very close in size and shape to what I needed. I also sourced some replacement springs.
The frost plugs were put in a lathe and sized to the proper dimensions to make them as accurate as possible and holes were drilled in the centers to receive the rod. Once assembled and painted no one would ever know.