In a half-ton truck, you should consider selling your truck and getting a heavier-duty truck with a dump. I think you'll find that putting money into a dump for too light of a truck will end up costing you more in the longer term.
A cheap way to help with the burden of unloading could be a Loadhandler. There have been some thread-talk about them.
Somebody built a box in the middle of the bed for chips, and had storage in the side areas. The box was the width of the LH tarp. This makes it a lot easier to use than if are going for full width, due to the "locked load" that happens with the wheel wells.
I overloaded mine and broke one plastic bracket (locked load) and too much gorilla grip.
A smooth bottom, such as without a grippy spray-in bed liner would be good, or if you have a spray-in liner, you can put a nylon tarp under the loadhandler sheet.
Also, if you find that the LH can't unload your whole box, find out what depth it can handle, then when you get that deep, lay a tarp in the box, and blow more chips on top. It will slide off with the additional chips, then use LH.
If you are chipping into your bed now, and unloading with pitchfork, you can change up to a tarp/chip/tarp/chip/tarp/ chip sandwich. Pulling about a foot of chips at a time is very quick and feasible with two people.