I needed a new outer axle shaft for my 91 YJ, so I got a used one from Jeff Daniels (local Jeep shop), and he gave me the whole thing, inner and outer shaft, with the hub/bearing assembly. However, when I got the hub off of the shaft, I sat it next to my old hub and it's slightly taller. The back of it is shaped a little differently, but it seemed to fit fine in my knuckle. I know at some point they changed the bearing type because my Haynes manual says that "early models" (soooo descriptive) can have the bearings repacked, but the "later models" are sealed. I don't know much of the vehicle history, all I can tell you is its what I think is the stock d30. The driver's side bearing has been replaced recently. I'm going to take it out and compare, but for now, here's some pics.
Old one is on the right, new on the left, you can see the newer one has a recessed bearing in a way
Old on the right, new on the left, you can see the different height