Although it is hard to find a copy of "The Mills Violano-Virtuoso" for
sale, it can be found in number of libraries across the country.  If
your friend does not manage to get a personal copy, check Worldcat for
the nearest library which holds the book: http://www.worldcat.org/ 

Worldcat has extensive coverage of public, university and other types
of libraries, in the US and around the world, making it very helpful
for finding rare titles.  Search the term "Violano-Virtuoso" to get a
list of all related titles, and you will find a number of publications
from Mills Novelty Company itself, and which libraries hold each of
them.

Meta Brown