Here's a Area Lighting Research 1/2" NPT threaded swivel mount thermal photocontrol with 1 inch cadmium sulfide eye.Also has a sliding shield to adjust the amount of light that can reach the eye.
The same photocontrol (minus the swivel mount) controlled the path lights at my parents' home the whole time I was growing up. It faced south....and while it never failed completely, it started coming on later & later until it was well after dark before it clicked on, so I replaced it a few years before I left home.