If the 'uniform' is just going to be a mantle, it's fine if it's just one colour. Mantles don't usually come in two tones, and when they have trim it tends to be made of fur rather than just being decorative. Sometimes they have one colour on the inside and another on the outside, though. Bram Stoker's Dracula--black mantle, bright red on the inside--is the most classic example.
Likes: Doshii Jun and Wes