As Cyrus stated #19, it isn't that WMO/17 is rare, they made a buttload of them in 1917 (bb-cc blocks, though the latter often are 1917/18 receivers); most clearly did not go to Turkey... just survival rates emphasize WMO/17 Turkish presence in survivors... what remains of 1917 non-Turk is interwar service rifles, often less than perfect.
Real deal WMO/17's in factory or Imperial trim are rare, especially bolt matchers. This is one of the finest (original-factory matching) WMO/17 known, that is what makes it desirable (that and its the premier G98 maker, only DWM comes close to WMO standards during the war and DWM had labor unrest in 1916-1917 - operating a factory in Berlin during the war had its downside!)
Real deal WMO/17's in factory or Imperial trim are rare, especially bolt matchers. This is one of the finest (original-factory matching) WMO/17 known, that is what makes it desirable (that and its the premier G98 maker, only DWM comes close to WMO standards during the war and DWM had labor unrest in 1916-1917 - operating a factory in Berlin during the war had its downside!)