A nice rifle, but I agree that it is a humper. The WaA63 parts were made by Mauser Oberndorf, not Sauer, and inspector #37 apparently didn't get to Sauer until 1939, so there is a lot of parts mixing. The buttplate, with its pristeen screws is just too good to be true and so is the lower metal (trigger guard and floorplate). The number fonts don't look quite right, either, and the stock has obviously been cleaned and sanded. A good generic K.98k, just not serious collector quality.
Jim