Depend which scale you are looking into.
There is a kit for convert the Tamiya Willys into a CJ3 this in 1/35, but I don't remember the name. If you want bigger scale you can look a the Mitsubishi-Jeep in 1/20 made by Academy. If you are looking in a 1/64 there is also the Mitsubishi-Jeep made by Tomica. Those Mitsubishi, are pratically CJ3, made in Japan under Jeep license.