S.B. - Good Eye! I like leaving the magazine cut-off in place on my Krags.
I have a Redfield #102 sight, that I 'adapted' for quick-change & easy use on some of my Range "Krags".
It is held on with just a longer (than issue) side-plate screw made from a 1903 Springfield swivel-screw.
To prevent movement and rotation of the Redfield sight-base, I made a replacement sheet-metal plate.
This plate mounts on the rear of the base and has a 'finger' that fits under the cut-off lever.
(The cut-off remains in place, but, cannot be rotated).
I have simply replaced the factory plate that 'hooks' into the cut-off shaft hole.
Sporterized and unofficial modified Krags