If you're not already familiar with it, this web site should be of interest. Here is a link to one of their pages which has som N.11 drawings.
This site also contains profile drawings and much other Nieuport information. You might also inquire from the publishers of the Journal "World War I" Aeroplanes at
World War I Aeroplanes, Inc.
15 Crescent Rd.
Poughkeepsie, NY 12601, USA
In addition to their Journal they have a "Master Materials List" (cost is $12 US) which is a listing of drawings and manuals pertaining to aircraft and engines. Copies of the drawings listed can be bought from them. I recall that the journal published some drawings from Macchi for their license built Nieuports; I'm pretty sure that the N.11 was among them.
Also, are you familiar with the Proctor N.11 model kit? It is smaller than 1/4 scale, approximately 1/5 scale I believe. Many have been built and flown successfully since the 1960s.
I hope this helps.