Just go to your local optometrist with your firearm, he can solve your problem. I'm nearsighted and can see my irons perfectly but that target was just a pulsating blur. Went to my eye doc with my 1911 - he put several lens in front of my eyes until the right pair matched up and I could see my sights and target at 200 yards perfectly.(Aiming out his office's window) It was like being 20 years old ago again.
Red Dot sights are great, as long as you keep your eyes/head in the same position shot for shot, as red dots are notorious for parallax - anywhere from 6 to 14 inches from extreme side to side. Most people will be fairly consistent with their cheek weld or eye position, shot for shot, so the damage shouldn't be more than 1/2" to 1" at 50 to 100 yards but with a 2 to 4 inch dot - that group can grow fairly quickly at longer ranges, so just pay attention to cheek weld on a rifle and head position with pistols.