OK Freebooter's Fate uses Cards not Dice, but not only do Dice focus with some import in "At Worlds End" - Dice are nice Booty to own in my own humble opinion.
Obviously you could buy a set of Official "Liars Dice" but to be frank they are just ordinary Dice in a Funky cup LoL!
One of my favourite Pairs of Dice are these from Q-Workshop, stunning D6's engraved with all sorts of Pirate Map Imagery - they aren't cheap, but if you surf Ebay you can find a bargain -
They even do a gorgeous Jolly Roger Dice Bag (my Freebooter's Fate Cards live in mine too) -
Em4 Miniatures in the UK and G2 in the USA have some nice basic Skull and Crossbones Dice - Some are Numbered, and others have Spots - so everyone's tastes are catered for (and they are quite cheap too) -