My guess is you could do the injectors 3 or 4 times for what a 7.3 swap would cost. You would need a complete donor motor, 4r100 trans, complete wiring harness with computer, the IDM, etc.... Then you run into the problem of things like gauges working and such.
Fix the injectors, sell the truck and buy a 7.3 would be a MUCH cheaper route to go imo if you are really intent on getting rid of the 6.0.
But honestly if you hit up a place like warren diesel or casserly (full force) you will get injectors that will last a LONG time if you properly maintain your truck. Just sayin...