With respect to the Dienst-Hupfeld player of Mr Iverson, it would help
if he could provide details of the roll width and tracker-bar hole
pitch.  I have experience of the early Hupfeld cardboard disc and roll
players, of which this clearly isn't one, and the 73-note paper roll
models.

The DEA of Miguel de Mattos is very rare and well worth restoring.
I believe that there is one in the British Piano Museum (Frank Holland
Collection) at Brentford in London.  I'm sure the trustees will help
you.

Kind regards to all MMDers from The Midlands of Great Britain.
Nicholas Simons