I'm doing a cheap and simple 2" lift on mine using the following Off Road Design Parts.
ORD 1" Body Lift,
[FONT=Arial, Helvetica, sans-serif]'81-'87 GM truck - #G231003 - $102.50[/FONT] ---
One Inch 1-inch Body Lift Aluminum Pucks from ORD Fullsize 4x4 Parts
ORD 1" zero rates, [FONT=Arial, Helvetica, sans-serif]
Part #U8001 (for 3" springs) - $[/FONT][FONT=Arial, Helvetica, sans-serif]
45.00[/FONT] ---
Add a Leafs, Zero Rate for 4x4 Suspensions from Offroad Design
Another Option would be ORD's Complete 3" lift system spec'ed out for a CUCV.
ORD Complete 4x4 Lift Systems & Kits - GM Chevy Leaf Springs
Why do you want to level it? I've never understood leveling, it just doesn't look right, as pickups are supposed to have a "raked " stance.
Pickups were designed to haul loads, and the factory stance accounts for this, so that most loads ride fairly level. The only reason I can think for leveling a pickup would be to give an extra bit of clearance for larger tires in the front, where it is more of a problem than the rear. Just my opinion.
Another good source for lift options would be DIY4X ---
DIY4X: Catering to those who enjoy doing it themselves., Kurt is always very helpful and would set you up with a customized lift to your specific desires.