The SSR weapons from raids? Until recently, the answer would be no.

...but it seems that on November 29, the DMM version got a new shop, allowing one to exchange orichalcum for old raid SSR weapons, presumably. I see Mjollnir from Jormungandr's event at least. 2 ori for one copy.
Of course, when it comes to orichalcum, you'd probably be more concerned with using them for final limit breaks... :P