The AGN App is ready! Search "Airgun Nation" in your App store. To compliment this new tech we've assigned the "Threads" Feed & "Dark" Mode. To revert back to a traditional "Forum List" view, and/or "Light" mode click HERE.
Forgive me for jumping in, but generally open and aperture rear sights can use the same front sight.
I may be misunderstanding your question, but all inserts for the front sight are centered on the sight tunnel, i.e. none are higher or lower than the others.