Well I'm fairly certain there won't be dye color restrictions on gear. My reasoning for this is that within the same type of gear the examples aren't consistent. Example:

Felt Coif is listed in Black and Grey
Felt Hat is listed in Green and Red
Felt Gloves are listed in Blue
Felt Barret is listed in Blue, Brown and Red

With the current dye tiers the color is consistent across the same material. I think this heavily supports the example theory.