ww1 Sextent Stanley London 1918 no.3717
After looking into the markings abit more and searching quite a few pages via google i managed to find out more about this item, i found one remarkably similar by Hughes & Son London.. better condition going for $1220
the similar one was found at this website
WWI Military Brass Pocket Sextant by Hughes & Son London. - Gilai Collectibles
i can get more pictures on request
I hope i can get more information on this as it was my late grandfathers.. he never actually knew what it was hehe