I wouldn't suggest getting one EXACTLY like any of the groups on your campus, but if you want a jacket, get a jacket. A few OPhiAs have jackets, the vast majority don't. It's not that big a deal, although it does get noticed. Chances are, your group will suddenly be that one NPC group on campus that the D9 orgs all actually remember their name
There's always got to be one, might as well make it yours.
(I would check the protocol about the crest, tho', as 33 already mentioned.)