Here’s a view of the left side, in better lighting, showing stock figure:
In this photo, the rifle is still wearing a Ruger folding rear sight (with the screws flattened), providing objective bell clearance about the thickness of typing paper. The better Marbles provides much more clearance, maybe slightly more than 50 thousandths.
If you enlarge this photo, you’ll just be able to make out the “ivory” bead front sight, which came standard on this 275 Rigby model. The also standard “express“ rear sight was necessarily removed, and stored away for later.