Thanks for all of the great responses and suggestions.
BoldBlue737: I've decided that your course of action is the correct one, at least for the time being. When I get the new array, maybe I'll tear the existing one down and see if I can locate a maker's stamp or barcode or something like that on the wind cup assembly. Also, maybe I can figure out how one would replce the cup assembly if it were available.
nincehelser: The issue is that the cups are put in place at the factory, and then a mast is installed above the wind cups and then the windvane above that, so that the wind cups are effectively captured in the assembly.
At this time, I don't know if that tower housing is removable or not. As things sit now, if I want to keep using the observerIP unit to report my conditions to WU, then I'll have to replace the entire sensor array. Ambient doesn't have the cups listed as a separate item on their website or in the owner's manual.