The problem is if the game can't find the exact piece (Say a yellow robe) It'll use a different one if it can (Same robe, blue with materia) and warn you it couldn't find the exact piece requested.

It could probably be done, but the spiritbond activates as soon as you finish a fight, that should be enough for the filter I mentioned to work.

Edit:

Wheres the guessing? if you're running that many classes you don't know which ones are using what weapon, you should sit down and organise it.