I went through this over a decade ago. I was not successful in finding a part number for just the joint. Looking at the digital microfiche it's not sold as a separate part number. The shaft is an assembly. NLA from Toyota. See pic.
I guess you could take one apart, take some measurements, and see if NAPA can match it up.
I've thought about taking it apart and pulling some measurements but I dont want to be stuck with a blown apart shaft and no replacement U joint. I have a feeling once I remove the joint(s) they wont go back in and function the way it is now. Might do a prelim still installed set of measurements. See if anything is even in the ballpark.
If I figure out a way to make a custom shaft, would I regret not building it with a rag joint?
Wonder if theres a dorman shaft available with proper ends or proper-ish ends that can be modified for length/whatver.