You get the base outfits by finishing A pirate's tail quest when you defeat Ratmiral Blackwhiskers.
To get the first addon you have to use a soap Which can be dropped from Tentugly's Head
To get the second addon you have to use a Scrubbing Brush
Both items are a drop from Ratmiral Blackwhiskers.
"Your deeds have been noticed and the following items dropped by Ratmiral Blackwhiskers are available in your reward chest: a scrubbing brush, a small treasure chest,-5 mastermind potions 10 great mana potions, d crystal coin, 10 ultimate health potions, 20 platinum coins"
Upon using both items you will get the achievement: Honorary Rascoohan