Nikon have had a long relationship with Sony for the manufacture of sensors. These days the Nikon marketing blurb generally says 'developed by Nikon' for all the new devices. I used to work for Kodak in the early days (circa 1996-2000) when there was a link between Kodak and Nikon, but to my knowledge that relationship is long gone. I would echo the advice of Daniel. Find a used body with a functional sensor and make the replacement by transplant. Taking apart the donor camera will also give you useful experience for the later disassembly of your original body.