[ Gary Heckman wrote in 100525 MMDigest:

> The rolls measure ten inches, the right side has a gear on the flange.

These rolls are for the Magnus Self Playing Organ.  This is an
American organette made in the early nineteen-fifties and operated
by mains electricity.  It plays a 29-note music roll and is fully
described on pages 253 to 255 of Kevin McElhone's Organette Book.
I'm sure you'll find a willing buyer amongst the American organette
collectors.

Nicholas Simons, GB