For anyone wondering, the DS-1280ZJ-XS & CBXS mounts should work for this camera. I'm using this one from Amazon: https://www.amazon.com/gp/product/B071F3TXQT/ref=oh_aui_search_asin_title?ie=UTF8&psc=1
According to the specs, the Hik should have a 78 degree FOV.
An IPC-HDW4231EM-ASE with a 3.6m lens has an 87 degree FOV.
Oddly, Dahua lists the focal length for the IPC-HFW1831E as 4mm, but with the same FOV as the 4231...