It would be impossible to replace the tracks without wrecking one side of the wall. It should be possible to remove just the door casing and remove the door though. It just depends on how it was built and where the stops are that center the door when closed.
Then again, You may have a center stop that is accessible without removing the casing at all. Look at the top track and see if you can see a stop block near the center of the door. If you see one, remove the block and pull one of the doors past center. You should be able to determine how much trouble it will be to remove it once you get it completely out of the wall
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