I too would go with the AR and do, sits right next to the bed, with the aimpoint on, at 1/2 intensity, also has backup weapon light.
The 5.56 is quite safe in the home, I have a small hole on the inside of my garage wall and a big 1 one the other side at the porch wall, gypsum wall plus 1/4" fir down with vinyl covering, the opposite wall, about 4', has only speckles in the vinyl around the porch lamp, glass was not broken. This was PMC bronze, 55gr fmj. Don't know how it got there. The 5.56 won't over penetrate, but neither will your choice of the .357 glaser safety slug, don't know how well it work in a lever gun, and as that is your choice, you can rubber band a good rear pressure switch flashlight to the forend, hell even duct tape it and it will work without buying rails, or blocking the sights. ( Rails are available you know )