The Model 69 and the Model 75 have identical actions, but various years had differing bolt & trigger styles.
The Model 52 is an entirely different design/breed of cat.
Some Model 69 triggers are slightly adjustable, via a screw in the rear of the trigger housing, accessible after removing the barreled action from the stock.
I have no clue, as to the origins of your globe/target front sight, which takes interchangeable reticles/inserts of various configs, like crosshairs/posts/circles/etc/etc.
If you GOOGLE the "Lyman 17 globe sight", you should see something similar to what your rifle carries, and the card of inserts that accompanies a new sight.
BTW - Winchester ofter installed Lyman sights as a factory option.
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