The lift kit should have reused the oem control arms, I know my Trailmaster 4" kit did. You can get new bushings here at
Summit Racing for under $40. It is a bit of a PITA to swap them out, expect to spend a good 6-8 hours per side when you do it. You have to drill or torch out the old bushings, remove the fused rubber from the metal components, and press the new bushings in. You can press them in at home using a large C-clamp if you freeze the assemble bushings overnight. You will also want to have two new torsion bar bolts and nuts on hand, the old ones tend to break when trying to remove them. If you have to use the truck for work, you can split the job up over two weekends, doing the lowers one weekend, and the uppers the following.
Given the age of your Runner, you will also want to replace the
Body Mounts.