Hmmm. The base that's on it now is pretty ugly. Actually it is far simpler than the rifle. The dovetail fits perfectly and the base is tapered upward on either end to a double folding leaf. The combination which is a Lyman, has a very deep v which folds flat and a flat leaf with no "v" of any sort , but a white diamond which points to center. Both fold flat.
The tang sight as described earlier is a lyman that attaches to the bolt release on the left. My guess is that the sight with the diamond is to realign the peep, as it has to be raised to remove the bolt. That front sight is a 3/8 dovetail
What is on the rifle now is certainly American. I can't imagine Mauser setting it up the way it is, but than again it is a commercial rifle in an American caliber (marked "us govt06".)

Tom