"Maybe" the belt is original (could well be but those photos are not enough to confirm it right away) and "maybe" it once belonged to H.Dorner (I let you handle that belief based on the hand writing shown on the belt). But, if the belt is later confirmed original, will remain the buckle doubtfuly ever fitted this belt. Then the buckle:
1- I would need a much better close up of its back to say if it is at least an original Emil J�ttner buckle and not one of the 2000's reproductions.
2- If original the repair job was likely made post war. If made pre-1945, the repair guy certainly been shot at time he remitted the repaired buckle to its owner.
3- If original and if the repair guy has been shot, then this buckle never been on that belt. But you have the paper to make you feel safe.
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