I got a "Lyman # 2" for my .45-60 rifle with 28" barrel several years ago.
I also replaced the original front sight for a Lyman Ivory Bead sight.
I believe I got mine from Dixie Gun Works, and that it was marked "for Win. M1876".
Now I can't find it on their site, and the closest I come are what Buffalo Arms Company has in stock...;
https://www.buffaloarms.com/target-44-iron-sights-optics/lyman.html(I'm thinking it would be possible to fit the one marked "for Win. M1886" to the M1876 too, but You might have to drill and tap a new hole in the tang. Possibly also tweak the upright angle of the tang sight.)
I have since added an offset scope mount and a 3X Malcom "short scope" from Leatherwood Optics.
The dust-cover and original rear-sight had to be removed to fit the scope.
By filing a notch/groove in the front scope mount I'm able to use the tang sight also.
Should You be interested in period scopes You might also want to check out OpticsPlanet.com in addition to Dixie and Buffalo Arms.