I have a Mermod Freres 11-inch "Ideal Guitare" interchangeable cylinder
music box with three cylinders.  The three cylinders are numbered G606,
G604 and G616.  Each cylinder plays 6-tunes.  The five-digit number on
each cylinder is in the 33000 series.  I have a chance to purchase two
additional cylinders, numbered G612 (48000 series 5-digit code) and G611
(50000 series 5-digit code).

Is it safe to both these cylinders play 6-tunes?  If so, would they be
compatible with my music box?  If, by chance, both cylinders are dated
older than my music box, does this really matter?

Any help is appreciated.  Thank you.

Rick Mazur