Very long distance Ethernet connection for internet and other data (2000 feet)

You want an Ethernet over coax extender like this one...

https://www.amazon.com/StarTech-com-Gigabit-Ethernet-Unmanaged-Extender/dp/B00AMCKN80/ref=as_sl_pc_ss_til?tag=joshcom-20&linkCode=w01&linkId=B6C47PTXNGHWHVUT&creativeASIN=B00AMCKN80

It should easily be able get you to 100Mbps @ 2000ft (~600 meters) using any supported coax cable...

100Base-FX seems to be right with 2km as its max theoretic distance, and there appear to be converters available at reasonable prices. Or is the termination problem one of attaching the connectors to the end of the fiber? I would have thought it was possible to just order one of the correct length.