Crécy Publishing, who now own the Hikoki imprint, are selling copies of the paint chip chart that was included with Michael Ullmann's seminal "Luftwaffe Colours 1935 - 1945":
http://www.crecy.co.uk/luftwaffe-colours-1935-1945-paint-chip-chart
At only £7.95 for 40-odd colour samples this is a bargain.
John