Well all you have to do to find them on the Nexus is search for "Psijic Robe" on the Skyrim Nexus.
Unfortunately, none of those do exactly what I'm looking for, so I'd have to do it myself. Is there a guide that shows how to mess with these? I'm wanting to add an Enchantment to the existing Psijic Robes, not replace the model of all Master Robes of Destruction with the Psijic Robes. Adding them to the Archmage's Quarters should be as simple as adding them to the inventory of, say, the Safe in the room, so that's not a problem. I just need to figure out how to add the enchantment I want to the existing robes.