Charles Davis asked, "Does anyone out there know where I might obtain
some build plans for a small crank organ cart, with a drawer for rolls,
similar to the ones for Raffin 20-note organs?"

I would suggest you look at "Carts for Small Organs" by Wallace Venable
(yup, me) on  http://www.melright.com/busker/jsart98.htm 

This is part of the John Smith Busker and Universal Organs web pages
maintained by Mel Wright:  http://www.melright.com/busker/jsmith.htm 

He has articles about the John Smith organs, including hundreds of
building tips at  http://www.melright.com/busker/jsmenu.htm 

There are at least three articles on carts, and you can get additional
ideas from the photos of various John Smith organs on another page at
the site.  While the articles here are focused on Smith organs, the
information has wider applicability, of course.

Wallace Venable