70 with a cataract with deteriorating vision. Lost right eye from a childhood accident. What are risks in having surgery & how can I find best surgeon?

Minimal Risks. Cataract surgery has advanced such that risks are minimal, but not non-existant. You should only consider surgery if your life-style is being significantly limited by deteriorating vision. Contact your state ophthalmological society to get names of highly skilled cataract surgeons.
Cataract surgery. The main risks of cataract surgery are infection and retinal issues. Fortunately, these issue are rare and your risk of seeing worse after surgery is around 1 out of 10, 000. I would recommend seeing a surgeon that performs topical small incision cataract surgery since you need your vision as good as possible as quick as possible post-operatively.