ID the part that needs replacing in the one of the online illustrated parts drawings and then place the PN into messick's. The PN details will also have a section showing what other models use the same part number. This will help answer your question.
What makes it somewhat difficult to answer your question directly is I'm not certain where the crack is and what you're calling the rearend. I believe the main section between the wheels is called a transmission by kubota and axle cases bolt to the transmission. Perhaps a picture of the damage would help.
You might want to delete your duplicate post (if possible).