Take a look at  http://members.aol.com/NEMRoll/mfg.html

This is the Comprehensive List of Player-Piano/Organ/Orchestration
Roll/MIDI Manufacturers/Providers list as I've received data to-date.
I'm still waiting for requests sent through the post to return.  Send
any changes in to me.  I've also added some new businesses that have
not responded.

They'll be categorized and delineated similar to the way the current
MMD list is structured.  I've not got to that step yet.  But this is
the general form it will take in the end.

Do not include this URL in your web page -- it will surely go away
later.  Wait until it is posted at the foxtail site in about a month
or so.

Karl Ellison