For the rear differential, can you switch out the passenger side axle with another GSL?

Or is it better to just switch the complete pumpkin + axle set up?

We have a new rear differential but mine looks a lot cleaner (not as much rust) but the axle / hub is bent or warped.
Plus if the axle is a lot easier it would help, since I am having trouble finding a friend's garage to work on my car.

 

there are two types of 12A axle, the small bearing 79-83 and big bearing 84-85. the brake hardware just gets slid over the axle

 

thanks!