Speak with "Silvermoon" Harry at Scalawag Point about the missing Vrykul artifacts.
The Northsea Freebooters all fear and respect Grezzix. I'm thinking they recognize my special talents and envy my amazing ship. All you need to do is tag along with my cabin boy, Lou, and you'll be in like... In like tin. Pirates love tin.
Just talk to Lou when you're ready to go and he'll take you to Scalawag.
Oh yea, you'll want to talk to "Silvermoon" Harry first. He'll have more information on the stuff they pilfered. Just watch what you say around him. He's a freak... crazy for blood elves.