Joyce Brite asks about replacing castors ( casters in USA ) on player
pianos.  I do this as a rule on every new piano I acquire.  The old
castors will be rusty and when rolled around the music room will leave
marks where they stick, and scratch a nice gouge mark in the floor.
I always use the best twin wheeled, ball bearing castors supplied by
Heckschers of London.

The easiest way to fit new castors is to do it when you are restoring
the piano and all the contents have been removed.  It is then not too
much of a problem to lay the piano on its back and fit the new castors.
First, put two thick planks of wood under the upright piano, sticking
out rearwards as far as the height of the piano, and then lower the
piano down onto its back such that it rests on the planks.  This will
make lifting it back up much easier.  You will need the help of two or
three strong men, but I find my friends are usually willing!

An alternative is to plan ahead when buying a new piano and have the
removals men deliver it on its end.  Make them a nice cup of tea while
you fit the new castors, which should only take a few minutes, and then
they can replace it upright and leave.  There was  no additional charge
when I did this a few years ago.

Good luck!
Nicholas Simons, GB

P.S. In order to comply with the gender equality regulations the use
of the word 'men' in the above is intended to refer to the genus
'homo sapiens' and not to any particular gender of that species.