Plain coconut water is literally just the water on the inside of a coconut. So if you can get coconuts at your grocery store you can get coconut water. I also found this recipe on how to extract and flavor the water: http://www.eatnapplay.net/2013/03/04/make-your-own-coconut-water/.
About Celebrity Solstice. Celebrity Solstice is a large ship, carrying 2850 passengers and 1246 crew, and sails from Sydney, Australia and Auckland, New Zealand.
Celebrity Solstice was, at 122,000 GT, the largest ship to be built at a German shipyard, but this record was surpassed by the Disney Dream, a 128,000 GT cruise ship of the Disney Cruise Line.