In this case, South Sea actually is a speck of an island and not a generic term.  One website gushingly writes  (slightly abridged):  “South Sea Island is a popular destination located in the Mamanuca Islands. The tiny island is just 30 minutes from Port Denarau, surrounded by crystal-clear waters and coral reefs teeming with marine life.  The island may be small but there’s plenty of room for everyone. South Sea Island features a dorm with twin bunks and sun loungers that sit atop the open-air restaurant. There are also stylish new double-bedded bures complete with outdoor en suites. You can spend the day lazing by the saltwater swimming pool, utilize the complimentary non-motorised watersports or explore Fiji’s colourful marine life from the semi-submersible submarine. There is nowhere more tranquil than this tiny island paradise.”  TripAdvisor reviews are really instructive and apparently if you don’t mind crowds you can do quite a lot there.  What you see in the card is the whole island.  Unused, 4″ x 8-1/4″.  Grade: 1