I'll be that she means the Singer Puzzle box that holds the attachements. Here's a listing from Ebay to give you an idea of what she is talking about.
http://www.ebay.com/itm/Vintage-Puzz...d=315270624361
I have been dragging my husband out to find machines. He comes along willingly when I promise to take him out to dinner. In the last month or so I have bought a 1915 Singer treadle 15-30 and a 1953 Black Singer 301 Shortbed in a Singer #42 cabinet. I have had so much fun cleaning up the machines and making them "sing!" I am waiting for warmer weather to refinish the cabinets!
Have fun! And let us know how this all comes out!