The photograph of Fred Prince next to a Nieuport 11 at
http://www.earlyaviators.com/eprince.htm also appears in
Cross & Cockade Journal Vol 2 No 1 of Spring 1961, where the caption indicates that it was taken while Prince was instructing at Pau. I've had a look through various books and journals for a photo of a Nieuport 17 flown by Fred Prince while with N.124, but without success.
I'd say that you can be pretty sure that Prince's machine was doped in overall silver/aluminium, with metal parts in their natural state. The unit insignia in the pre-April 1917 period was the head of a Seminole chief (see below). It was changed to the more familiar Sioux chief after the US declaration of War. See Norman Frank's
Nieuport Aces of World War I, ISBN 1 85532 961 1, for a colour drawing of the Nieuport flown by Sgt Raoul Lufbery of N.124.
I hope that this helps you.
Gareth