I did not notice anything of importance in the local listings. Petco or PetSmart I don't remember which. Hawaii has restrictions on what can be kept in the aquarium to the point of limited fish and no corals whatsoever. So Hawaii sucks for stores and livestock.
The only exception is a visit to the local seahorse facility. This is worth the time and small expense. Plus you can get information on ordering seahorses for your aquarium from them. Ocean Rider at www.seahorse.com they now have leafy sea dragons they are trying to breed on site. .