What you need is a pair of lenses with the primary (top) lens with an intermediate distance focus, not look thru a close reading lens like most bifocal lower lens. I use bifocals that are set up for computer use, with an intermediate lens on top, and normal reading lens on bottom. Actually I use them all the time since I can see nearly perfectly at long distance with them also.
If you look thru the bottom of a bifocal, you can't eve begin to get a clear or nearly so, target.
These give me an effortless focus on the front sight, with a slightly blurred target. Just like a kid should see.
Eye dominance won't be a problem unless you try to shoot rifle or shotgun with crossover dominance. You just can't get your head in position to do that. It is always nice to be right/right or left/left, but lots of folks shoot handguns sucessfully with crossover. Seems real awkward to me, but right to them.