5mm is what you want, if you don't have one there is a dive shop near the Naha Port,
日本最大級のダイビングショップ|エムアイシー21(mic21). mic21 will have anything and everything scuba. When it comes to dive shops in the area:
SEASIR NAHA is a long standing diving shop in Okinawa. We go diving all year round at the Kerama National Marine Park. We also provide drift diving and expedition diving for advanced divers.
www.seasir.com
ファンダイビング、体験ダイビング、そしてスノーケリングなど、沖縄の美しい海を存分に楽しめる「coco ocean沖縄」。初心者から上級者まで幅広いコースを提供しており、少人数制で安心安全をモットーに低価格のサービスを提供しています。
cocoocean-okinawa.com
那覇でファンダイビング。格安料金で初心者も半日からダイビングするなら「DiveStar」にお問い合わせください。那覇市でダイビングツアーやライセンス講習などを、地元の方や観光のお客様にご提供しております。レベルに合わせたメニューをご提案しておりますので、どなたでもお気軽にご参加ください。
divestar-okinawa.com
if you are looking for the middle of Okinawa, these are the places I recommend:
Okinawa 39ers is a bilingual diving operator in Okinawa. We offer the Kerama islands dive trip, USS Emmons, intro diving at Blue Cave, certification courses, etc.
www.okinawa39ers.com
Aloha Divers Okinawa are PADI Instructors. Providing the best service and diving you can do in Okinawa. We offer scuba diving, diving course, diving trip, discover scuba diver and snorkeling. We serve in 4 languages. English, Portuguese, Japanese and Spanish.
www.alohadiversokinawa.com
Okinawa based international diving service. Kerama islands boat diving, Beach diving, tech friendly, Certification courses, instructor courses, Yonaguni Dive trips. Mandarin, Cantonese, English, Portuguese, Spanish available
www.reefencounters.org
Were are the premier, English speaking dive company here on Okinawa! Available at short notice and able to take great care of both Experienced and beginner divers! Lets enjoy the beautiful blue waters of Okinawa together ;)
englishempiredivers.com
Dive with Sunkissed Divers in Okinawa and experience the difference between commercial diving and a personalized scuba diving experience. Mob +81 080-4691-5036
sunkisseddivers.com
****By all mean, these are not in any particular order***
If you have any more questions do not hesitate to hit me up.