I'm sure that if you look on some used book sites, such as addall.com or maybe amazon, you can find it. It is an excellent work.
Faberge in America by Geza von Habsburg
Thames & Hudson, 1996 ISBN 0-500-01699-2
According to the book, the other items in the Minshall Collection of Imperial provenance (not including the nephrite miniatures):
the Red Cross Easter Egg, the square yellow guilloche frame (from Nicholas' study), hand-seal with purporine handle (belonging to Alexandra), frame for 9 miniatures (belonging to Alexandra), Kremlin Tower Clock (Nicholas'), Miniature Cup in gold.