Hello,  S.M. stands for Schüller & Meissner from Leipzig.  We have
several of their catalogues in our collection, as well as about 1,500
rolls, most of them 88-note.  They also produced 65-note rolls, and
we also have a few 73-note rolls with the SM label.  Some late 88-note
SM rolls are identical to Hupfeld rolls, so they may have been made by
Hupfeld.

During the First World War the Choralion Company sold SM rolls with a
Themodist line because they could not be imported from the UK.

Kasper Janse - Pianola Museum
the Jordaan, Amsterdam
https://www.pianola.nl/