Flamberge - 2K, simply because it's a max damage sword. The furious mod, if you salvage, will sell for about that amount.
Gladius - need to know the requirement, but as long as it's low, you can probably get 3-4K for it.
Pc on some weapons (gold and purple only)
Jetdoc
derrtyboy69
I would personally merchant everything, but salvage the +hp weapons