Just because they dont have the factory trussing and such, doesnt make them worth less. How much does an axle truss cost from a vendor? $25? You can make one for cheaper if you have the right tools.
This is the truss on the newer style (84-85) axles located on the bottom of the longside axle tube. yes the top gussets can be purchased from any toy 4x4 aftermarket dealer like Marlin