My guess is that it was for a specific Omani military unit. I couldn't find this specific coat of arms online, but it does depict the Khanjar dagger, which is on the Omani crest.

The khanjar is the traditional dagger of Oman.

http://en.wikipedia.org/wiki/Khanjar

https://www.google.com/search?hl=en&q=oman+army+coat+of+arms&bav=on.2,or.r_gc.r_pw.r_cp.r_qf.&bvm=bv.42261806,d.d2k&biw=1424&bih=734&um=1&ie=UTF-8&tbm=isch&source=og&sa=N&tab=wi&ei=R9MbUfH7GoqK0AWYv4DABw#um=1&hl=en&tbo=d&tbm=isch&sa=1&q=khanjar+dagger&oq=khanjar+dagger&gs_l=img.3..0j0i24.14642728.14643602.8.14643711.8.5.0.3.3.0.103.371.4j1.5.0...0.0...1c.1.2.img.ZiK7x-ydLbs&bav=on.2,or.r_gc.r_pw.r_cp.r_qf.&bvm=bv.42261806,d.d2k&fp=27657f6e2413c641&biw=1424&bih=734