deviategs

I have searched and found transmission swap threads, but not seeing much about driveshaft interchange besides talking about the 3 bolt flange vs splines.
I am getting some noise and vibration in my '94 that I am almost certain is related to the driveshaft. I'm not sure if it's the u-joint or carrier bearing. I went underneath and was able to twist the shaft back and forth a bit so there was some play. I wouldn't think that is normal.
So the dealer wants like $1500 for a new assembly, and I found the one piece shaft from a couple places online for about $300 + the adapters which is decent. I called a couple local shops but they weren't willing to help me.
But it's 50% off day at the junkyard this weekend and I'm planning to go anyway for some other parts, so which cars would interchange with mine? (or is pulling a 25 year old driveshaft off and hoping it's better than mine a dumb idea anyway?)
There's a couple of '98 GS's there but I think it has a different tranny than mine? But maybe the driveshaft is the same? There's a bunch of SC400s and a couple LS400s also.
Will any of these work?