Lenny, For that area, Rawlins is going to be your best bet. Although I drive through Rawlins quite a bit, I rarely stay there. I did one overnight at the Western Hills Campground and recall they had lots of long term visitors, so I assume theyre open year round.
That area of Wy gets mighty cold and windy in winter, plan for some thorough winterizing. We (my employer prior to recent retirement) built some of those wind power projects out of our Casper regional ofice.