Add different sizes for different parts of costumes

Not all costumes come as one full outfit. Sometimes you have to order leggings in one size and the leotard in a different size. However at the moment you are only giving one box to put one size for the entire costume. What if the costume is made up of different parts from different suppliers? Cargo Pants from Weissmans but a t-shirt from Walmart. It would me nice if there was a way to log all different sizes to the different parts of the costume, as not everyone buys generic costumes from a catalogue