After doing some poking around, I discovered that "Arctic Radio" is located in Cambridge Bay, Canada. It has that callsign west of 88 degrees west and goes by "Baffin Radio" east of 88 degrees west. It's located in the NAT-D region. There's also a NAT-D one that isn't mentioned on the wiki page: "Rainbow Radio". It's a military station located in Tors Cove, Newfoundland.
Here's what I've found so far:
ANDERSON RADIO (Guam)
ARCTIC RADIO (Cambridge Bay, Canada-west of 88 degrees west)
ATLANTICO RADIO (Recife, Brazil)
BAFFIN RADIO (Cambridge Bay, Canada-east of 88 degrees west)
BALI RADIO (Bali, Indonesia)
BANDBOX RADIO (Nieuw-Milligan, Netherlands)
BODO RADIO (Bodo, Norway)
BOYEROS RADIO (Havana, Cuba)
BRISBANE RADIO (Brisbane, Australia)
CANARIAS RADIO (Las Palmas, Gran Canarias)
CARRASCO RADIO (Montevideo, Uruguay)
CAYENNE RADIO (Cayenne, French Guiana)
CENAMER CONTROL (Honduras)
DAKAR RADIO (Dakar, Senegal)
EZEIZA RADIO (Buenos Aires, Argentina)
GANDER RADIO (Gander, Newfoundland)
ICELAND RADIO (Reykjavik, Iceland)
JAKARTA RADIO (Jakarta, Indonesia)
JOHANNESBURG OCEANIC (Johannesburg, South Africa)
KHABAROVSK RADIO (Khabarovsk, Russia)
KINLOSS RADIO (Lossiermouth, UK)
KOLTSOVO RADIO (Yekaterinburg, Russia)
LIMA RADIO (Lima, Peru)
LUMPUR RADIO (Kuala Lumpur, Malaysia)
MAGADAN RADIO (Magadan, Russia)
MALQUETIA RADIO (Caracas, Venezuela)
MANILA RADIO (Manila, Philippines)
MERIDACOM (Merida, Mexico)
MONTREAL RADIO (Iqaluit, Canada)
MURMANSK RADIO (Murmansk, Russia)
NADI RADIO (Nadi, Fiji)
NEW YORK RADIO (New York City, NY)
PETROPAVLOSK RADIO (Petropavlosk, Russia)
PIARCO RADIO (Piarco, Trinidad and Tobago)
PUERTO RICO RADIO (Salinas, Puerto Rico)
RAINBOW RADIO (Tors Cove, Newfoundland)
ROBERTS RADIO (Monrovia, Liberia)
SAL RADIO (Sal, Cape Verde)
SAN FRANCISCO RADIO (San Francisco, CA)
SANTA MARIA RADIO (Santa Maria, Azores)
SANTIAGO RADIO (Santiago, Chile)
SEOUL RADIO (Seoul, South Korea)
SHANWICK AERADIO (Shanwick, Ireland)
SINGAPORE RADIO (Singapore)
SVALBARD RADIO (Spitsbergen Islands)
TAHITI RADIO (Tahiti)
TOKYO RADIO (Tokyo, Japan)
TURKHA RADIO (Turkhansk, Russia)
VIPER RADIO (Port Sandry, Falkland Islands)
WEST COAST RADIO (McLellan AFB, CA)
I don't know about the spelling of some of these; the map I found them on (mentioned in an earlier thread) had really small text and using the enlarge feature on my computer only turned the text into giant pixels.