+15% stance items are hard to sell, I wouldn't even bother but merch them both (after salvaging 20/20). They're however worth somewhere between 5-10k imo.
Golestandt is right, however I would attempt in auctioning first, You could sell you Saundering Jade Sword of Fortitude anywhere from 5-10k, put it up on auction and see if anyone bites. If a no go after a day or two salvage your 20/20 (first) then merch.