Thanks, Folex, for sharing the BTG-Audio link! However, I conducted a little research there and learned a couple of things worth sharing:
1) Brian is no longer taking orders due to a backlog of pending orders.
2) On his contact page, there's a list of headphones he does not service, which, sadly, includes the HD 380 Pro.
However, he also states that he does retermination (plug replacement) on all headphone cables. Hope this helps...