Krohne Level Displacer BW25

For this sort of purpose, perfectly satisfactory (usual disclaimer).

Yes, it'll work, (it's Krohne, so you pay for respectable German engineering). But it's mechanical. Mechanical stuff usually requires maintenance over time. In the US, the drive is to reduce maintenance because of the cost of maintenance personnel.

Displacers are still used extensively for interface measurements, because displacement works so well, but for simple water level, I have used a submersible head pressure sensor, a power supply and then do whatever is needed with the 4-20. As long as a submersible head pressure sensor doesn't get buried in the bottom mud, it'll work forever.