Driveshaft Compatibility?

Hi, I'm not on here too often, and I'm sorry to just post a new thread on this, but I couldn't find any solid info on this topic.
What Drive shafts can be used with the 4eat in a 2006 outback?
The u-joints in my dad's car went bad, so its time for a new driveshaft, but i cant find any quickly in my area, that are meant for a 4th gen legacy/outback.
So, what other 4eat driveshafts will fit a 4th gen., i can get my hands on a 2nd gen. driveshaft for a decent price, will that work?
Can i use one from a 4eat impreza?
Any help is greatly appreciated!