Severus gives it a glance, and shrugs. "For two knuts I could replicate that. The design is simplistic, if not unpleasing, and, as the casual glance reveals no special properties, even if it has the meaning you claim for it and is not merely some knock-off of the sigel of that American Muggle University found in a pawn shop, a forgery credible for most purposes would be the simplest thing in the world to duplicate using only base material, wax or clay, and a sufficient heat source."
"Neither," he says ominously, "are we. Your purported Unseen University has no reputation in Britain, or indeed Europe, assuming it exists. I believe you will find that the same cannot be said for the Hogwarts School of Witchcraft and Wizardry."
He smiles again, exactly the same sort of smile, only chiller. "You would prefer, perhaps, sausage?"