We usually drop the fraction when talking about a lot of the disc boxes
when there is no closer size that it can be confused with.  For example,
a 15-3/4" Regina is usually called a 15" and an 18-1/2" Mira is usually
called an 18".  A 22" Polyphon will never be confused with a 19"
(19-5/8") or a 24" (24-1/2").

Craig Smith is correct; as with 90% of most disc boxes, you can only
use one particular disc on a given machine.  Original 22" Polyphon
discs are very hard to find with the bell projections intact.  The bell 
linkages give so much resistance that usually many of the bell
projections are torn off.

There are two firms reproducing discs for this machine:

  1) Dave Corkrum <polyphonmusik@att.net.geentroep>
  2) Renaissance Discs in England <lesterjones@jscali.co.uk.geentroep>
  [delete ".geentroep" to reply]

Enjoy the holidays!

Nancy Fratti - Nancy Fratti Music Boxes
Canastota, New York, USA
http://www.nancyfrattimusicboxes.com/