Don't forget one oiling method that was very widely used and worked
perfectly for decades.  I have found them in many pipe organ blowers
and other motors large and small: the ring oiler.

The sleeve bearings had slot in the top of the bearing mount in the
middle of the bearing, where a steel ring of larger diameter was
inserted and loosely sat on the shaft.  It turned on the shaft and
also dipped into the oil well on the bottom.  Every time the motor
ran, it constantly supplied fresh oil to the bearing.

Keep the oil well clean and the oil level up and you could forget
them for years -- not thick, sticky oil but 40-60 weight non-detergent
motor oil.

Jim Crank