[PLUG] Simple/cheap linux-based 2000ft wireless internet bridge?

[Noj]

My friend lives on the river. On one side is a house that can't get
cable internet, and lost even basic wired phone service (barely worked
for years, went out completely for area during a flood). My friend has
been getting by on a cellular data widget, but it's only good for
email and service is flaky. 2000ft away across the river is another
friend's house and business, with wicked-fast unlimited internet.

I'd like to think a pair of linux raspberry pi's with the right
config, maybe tied to a pair of alfa usb-wifi devices with directional
antennas could make this perpetual run-around with the
lack-of-service-providers go away and bring the modern world to the
river house, but I'm only passingly familiar with the elements
involved.

Is this a viable start? Am I even looking at the right gear? Is there
any simpler way to make a rock-solid internet bridge?

Ideally the setup would be to just a pair of headless boxes, plug in
power and ethernet on both ends, and have it act as a long cable,
letting the desktop computer on one end get DHCP service from existing
router at other end.

I happen to have a pair of unused pi's, anything else I would have to
buy anyway, I'm wide open to any suggestions if you have experience
doing this kind of function with different gear.

noj