I wouldn't waste time looking in junkyards--since they started using forkloaders to lifr vehicles ,just about every rear wheel drive vehicle gets the drive shaft kinked or dented when they hoist it off the flatbed ...unless you happened to find a truck someone just drove in they hadn't tried picking up yet,you'll be hard pressed to find one thats not bent up junk...some really old yards pulled driveshafts and saved them,but its not fun going thru piles of them trying to find one like yours...
I have used a few car deiveshafts in GM trucks,had to shorten them though--I have a place I can get that done pretty reasonable not far away..
A good driveline shop can cut off your splined end and weld a new one on and balance uit,but it'll probably run you 150+ bucks,the spline alone is probably close to 100 bucks if not more...sometimes they wont charge much more to just build you one from scratch..
Surely there must be SOME place that has a lot of NOS driveshafts piled up like cordwood!..tried a google search??..