Single Driveshaft Swap

[MrToby]

Hey all, new here. Just got a 1986.5 Hardbody, my first Nissan, and it needs a little work. This looks like a pretty good place, figured I'd ask a couple questions if y'all don't mind.

It's a standard, and when I accelerate from first there's a pretty decent shake, I can't really tell where it's coming from though. Guy who had it before me said it was the rear end, another mechanic said it was probably the flywheel, a third mech said it was my carrier bearing. I looked at the bearing and I can't really see much rubber, so I'm assuming that's it. I need to fix it pretty quick and I was wanting to just swap in a single axle rather than the dual. It's not lifted, and it has the king cab with the six foot bed. Anyone know where I can find the d/s length? And what vehicle I could pull one from that would fit? I can't afford to have one made.

That was a bit longer than I intended so I'll just stick with the one question for now. Any info you all can give would be appreciated.