The second point is the date of it. The Haversack is clearly dated 3/44 (March 1944) and the strap 2/44 (February 1944), so WW2 manufacture for sure. The head harness on this example would seem to be dated 6/64 (June 1964). The date of the rubber mask is also usually moulded into it, normally in the area of the right cheek.
I would have to say "no, it isn't" to your question...
Rob has covered it.
Danish Army re-issues of these were £10 each at Beltring this week.
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