The full breakdown of the Pacific (excluding Australia, PNG and New Zealand) leaves 13 countries these are:

Cook Islands (Aitutaki, Penrhyn, Rarotonga)
Fiji Islands
Kiribati (Gilberts, Tarawa, Ocean Island)
Marshall Islands, Republic of (Eniwetok, Kwajalein, Majuro)
Micronesia, Fed.States of (Caroline Islands, Chuuk, Kosrae, Pohnpei, Yap)
Nauru
Niue
Palau, Republic of
Samoa
Solomon Islands (Guadalcanal, New Georgia, Tulagi)
Tonga (Nukualofa)
Tuvalu (Ellice Island, Funafuti, Vaitapu)
Vanuatu (New Hebrides Islands)

In addition to the 13 countries there are a further 23 territories. These are:

Austral Islands
Bismarck Archipelago (Admiralty Islands, Bougainville, New Britain, New Ireland)
Chatham Islands
Easter Island
French Polynesia (Gambier, Tahiti, Tuamotu)
Galapagos Islands
Guam
Hawaiian Islands
Juan Fernandez Islands (Robinson Crusoe Island)
Line/Phoenix Islands (Canton, Christmas, Enderbury, Fanning)
Lord Howe Island
Marquesas Islands
Midway Island
New Caledonia & Dependencies (L’Île-des-Pins, Loyalty Islands)
Norfolk Island
Northern Marianas (Saipan, Tinian)
Ogasawara (Bonin, Iwo Jima, Volcano Island)
Pitcairn Island
Ryukyu Islands (Okinawa)
Samoa, American
Tasmania
Tokelau Islands (Atafu, Fakaofu, Union)
Wake Island
Wallis & Futuna Islands