One thing that often helps with older shooters is using a fiber-optic front sight. These stand out both brighter and sharper on targets and game.
This ^^^ has worked well for me.
I will occasionally shoot whitetail does with a trio of late 1940's vintage Winchester 94s in 25-35, 30-30, and 32 WS that have Lyman peep sights and Williams Firesight front sights.
The 25-35 was under the Christmas tree over 50 years ago and came with a big, bordering on huge, white bead front sight that covered all of the black on a 100 yard target, but was easy to see in low light conditions as long as there wasn't much snow on the ground.
