Fixed wireless (11/24/60 GHz point-to-point antennas) is pretty good, and the hardware would be a few thousand, but I wonder if there's an issue with the funding where it needs to be actual fiber for some reason.

My first job out of college was at a fixed wireless ISP which was started by a guy with a story just like the OP.

This was 20 years ago now, but the service was very reliable using Motorola radios. Relatively low bandwidth (4-6mbps, not bad for the day) but you could on a good day do that at a few miles out.