I have a Lyman #57 SML aperture receiver sight that took a bit of shimming and inletting to fit. If your receiver is round I believe the Lyman #57 will fit. I use the #17 AML with inserts the height as I recall is .445".
Another sight to look into are tang sights that flip up and down that you may like as well though I've not found them to be as precise for distance shooting but are quick to use for hunting. My 1874 Sharps has a tang sight mounted on it with an faux ivory insert front blade it is quick and deadly on deer.
Edited to add: In the past I have found the customer service people at Lyman very helpful in sight selection for any application. There are different size beads ie. 1/16 or 3/32, heights, widths etc. their toll free # was 1-800-225-9626 give them a call my knowledge of their product line is limited to my own selection.
Last edited by Bloodline; 02/06/11.
