Dutch East Indies: SAU CIE stands for Saupers Companie ( Sappers Company, ie, Engineers)
(The Dutch language has many Military Terms of either Frenchicon or Germanicon Origin.)
I have a M95 Dutch Carbine with the same Marking.

The use of the horizontal tag is typical of KNIL Unit tags, and carried over into Indonesian Use ( they didn't bother to remove them after Independence, so when surplussed, they still has the Dutch ID markings). Indon Police Districts are usually "Branded" into the Butt.

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