If you ever do find usable spindles, do yourself a favor and Loctite the outside of the bushing, being careful not to let the Loctite to go everywhere. Use the kingpin as an alignment tool until the Loctite sets up.
Doing this will preserve your spindles forever.
It may however cause more wear to occur on the inside of the bushing where it rides on the kingpin, since the bushing will no longer turn inside the spindle bore. Keeping up with the 1,000 mile interval of greasing the spindles should give you a very long kingpin bushing lifetime.
Carl
