The SN on the bolt, and I believe other parts of the bolt assembly, should match all other numbers to be considered all matching. The Eagle stamp would be German. Bluing was the correct procedure at the time. I don't believe the phosphate finish was added until 1945. Should have a flat buttplate and I believe in the white. Are there any other markings on the top of the receiver like S/42 or 42, S/147 or 47? Is there a number under the eagle on the bolt stamp close to the breech? Any other info would help.
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