You can run aftermarket, or cheap out like me and get a factory 3/4 ton bar. I bought a used bar and went with new hardware and bushing for about half the price of an aftermarket bar.
The factory "stands" on the frame are riveted on. You don't really need them since you are lowering the truck. You have two options there. You can use the ECE lowered stands
(link) or you can bolt the clamps directly to the frame.
Since you are going with a mild drop, I would think the lowered stands would give you the best alignment and possibly prevent binding. That's just opinion though as there are several that have mounted them to frame with no stands and haven't had a problem.
