Well CimTel as they are known here (I call them Elmer Fudd Phone Company) is a small town phone company and a part of MBO INC out of Lawton or Oklahoma City. They cover about 5 small town communities and parts of 2 Counties Creek and Pawnee. I have ask them several times as has many others on my road and were told to many rocks to run Fiber. Funny though there are rocks everywhere out here it is our number one crop other than ragweed.
I hear you about rocks. I'm on a mountain that is nothing but rock with maybe a foot or two of top soil. I was saying something like this interfaced to the fiber. Probably many others with less power that would do the job. Small solar panels are cheap to run it and small battery for nighttime and cloudy days. Add an inverter, put everything in a weather tight box and good to go. Even if costs for everything came to $500, which I seriously doubt, it could be worth it long term.
I would think there is already something on the market to do the job. Maybe not.