Dear MMD,  I am rebuilding my late 1920s Steinway LR Duo-Art pump.
It is the 17" model with the stamped sheet metal crank arms and 1"
spacer blocks on each bellows.

I need to replace the main crank bearings (the ones that fit into the
heavy, cast plate) which are 17 mm ID, 40 mm OD and 10 mm thick.  They
are unsealed and are sort of like bicycle cone bearings where the inner
race and ball ring come out one side of the outer race.

I am told by my local bearing supplier that these are not standard
and require special ordering at about twice the cost of the standard
bearings which are 12 mm thick.  The special order 10 mm bearings are
also not sealed, whereas the 12 mm bearings are sealed.

Has anyone had this experience and, if so, what was your solution?

Thanks,
Pat DeWitt, Fort Wayne, Indiana