Don't just assume reconstruction is best for you since it has to be covered by insurance. I am so glad to have avoided addtional surgeries, complications and feelings of "foreign boobs." It's not something I'm comfortable with for myself. But I know women who have been made to feel reconstruction is necessary in order to "feel like a woman" or "feel whole" and I am one of a number of women here to say that simply isn't so. Foam prostheses work just great for me!
Cancer showed up in my second breast just in time for me to say remove them both at the same time. I'm with others in that I wanted all the potentially suspect tissue removed. Having been diagnosed with breast cancer, I had the opportunity to have it all cut off my body, even though I was told I could go with lumpectomies and radiation if I chose. I'm extremely glad about the decisions I made. I did not make them because of my doctors; I made the decisions I did based on doctors' input, pathology and my own intuition. In the end, I have excellent range-of-motion and potential physically, shortest recovery and best long-term prognosis. I would think that a double mastectomy instead of a single would not increase recovery time needed. But a single would limit your options a bit regarding size choices, symmetry, etc.
Regarding insurance and a mastectomy for a second breast that "is not indicated," I do know of some women who have had insurance deny coverage to remove a breast that still tests out healthy. If I were you, I would get answers about that directly from your insurance company in writing.
Good luck! I hope your research in advance really pays off for you. :-)