Here is a link to a website to find articles in Presto and Music Trade
Review about 1920's reproducing pianos and musical instruments.  Type
what you want to search for in their search box:

http://www.arcade-museum.com/library/search-music/ 

This search is set just for Ampico:

http://www.arcade-museum.com/library/search-music/search.php?query=Ampico&type=and&results=10&search=1 

Andy Raymond