Before you spend a lot of money on new lenses try this....buy Stick on Bifocals.com ...they are reading lenses that are plastic that are designed to place on your regular glasses at the bottom for reading. They adhere with just water, easily pop of when your done and can be used over and over.
Go to to the Pharmacy and pick out the reading glasses that allow you to see you front sight clearly through the top of your regular glasses(I don't recommend you bring your gun with you for obvious reasons) Just extend your strong shooting arm, stick out your index finger and make sure you can focus on the tip of the finger, that should be close enough. Make a note of the power that works and buy a pair Stick on Bifoculs on line. When you get them cut one to fit correctly at the top inside of you lens for your dominant eye. This will imitate what you doctor wants to do. See how this works for you and then decide if you want to go and spend the $ for a new lens or buy more ammo.