Maybe you could put in a leaf spring 8 lug Dana 60 from a 70's truck. Not sure if the width is right. I think you can get a 3.50 gear set for the Dana. You can get a 3.23 gear set for a GM 14 bolt 8 lug truck rear end. Might be easier and cheaper though to conver it to 1/2 ton axles.
1959 Apache 3200, Standard Cab, Big Window, Fleetside, 235/3spd, Original Paint
1964 C20 Standard Cab, Fleetside, 283/Power Glide, A/C, Pwr Steering, Pwr Brakes, NoSpin | 
