By leveling kit, are you wanting to lift the front, or lower the rear of the truck ?
If you are wanting to lower the rear then just flip the rear shackles and that will put you in the ballpark.
However if you are wanting to lift the front, I would say a set of coil spacer will do the truck good.
Lowering the rear = a couple of hours in the driveway/garage, and about 20 bucks for some good grade 8 nuts and bolts.
Lifting the front = a couple hours in the driveway/garage, and about 40-50 bucks for the spacers. I have seen them go on Ebay fairly cheap and often, and You can also get them from most of the lifted suspension manufacturers.