I don't think anyone has done any team colored Cavalry (at least not to the extent of the whole uniform). Nothing that I have seen in other mods and in the database anyways... I of course might have missed something, but I haven't seen anything like that.
You'd actually probably have better luck finding the base model (the guy on the horse is probably a standard infantry type) and finding a standard infantry that is made in the color you want (say blue)... you could then swap-out the DDS file for the rider and get the effect you seek... in other words, look at the DDS files included in that cavalry download.... if you see the rider is "rifleman_128.dds" or something like that, any "rifleman_128.dds" file would work in it's place (and chances are someone has made one of the color you seek).
A third option... change the DDS file to a PNG or BMP file and color it whatever you want in a paint program, change it back to DDS, and you get what you want... something like this is exactly how I started on that path.
