Wow, being a gear guy, I just looked up your gearset...3:31 appears to be kinda bastard. You are definitely best off finding a good used one. If as you say it all laid in the mud for a long time...everything in it needs replaced...I personally would find a chev 14 bolt 1/2 ton 6 lug axle....many more options, more available...
Driveshafts for all Jeeps, Constant velocity rebuilds, Replacement, Repair
Putting this back up. "Someone is gonna have to crawl under the rig"