There is a gentleman in Burnsville. MN. that used to run a fire museum and still collects old trucks and parts. He has a pile of solid rubber wheels and "tires" in his back yard that may be exactly what some of you are looking for! Many came from old Seagrave and American LaFrance trucks, but I am sure you could swap. He also has a large collection of chain drive parts, wheels, axles, etc. 3 huge buildings packed to the ceiling... He is motivated to move the stuff out of his collection, is open to cash, and is spirited! PM me or reply for details. I have been helping him move things around in his sheds this past month and am astounded at the amazing collection of old truck parts he has accumulated in his 80+ years of adventures.