Has anyone ever investigated using replacement shaft material? McMaster-Carr stocks ceramic rods and many flavors of plastic rod stock:
http://www.mcmaster.com/#raw-materials/=10vpk6o
There are probably other suppliers. McMaster is just one that I'm familiar with.
I guess the shaft width is the critical factor. Perhaps someone with a caliper could measure it.
If nobody sells rod stock of the right diameter, it seems you could put a larger rod in a lathe and mill it down to the right diameter. Ceramic isn't very machine-able, but the right kind of plastic should be.
Phil Nelson
Phil's Old Radios
http://antiqueradio.org/index.html