The 4.7-inch CAT S31 is now available in the US via Amazon for around US$330 and, although its specs do not match this price range, the IP68-rated water resistance and its compliance with the MIL-SPEC 810G standard for ruggedness make it a worthy choice for those who face tough environments frequently.
https://www.notebookcheck.net/CAT-S31-rugged-smartphone-finally-available-in-the-US.271926.0.html