Hot Spring in Oedo Onsen
Enoshima Island Spa would be a great choice for you, and probably just in case when you want to try another spa closer to the Metropolitan area in Tokyo, I'd suggest you try Ooedo Onsen Monogatari Hot Spring (Literary meating; Tokyo Spa Story), which is located at Odaiba, in the Tokyo Bay.
The best thing about this Spa, I reckon, is you can choose your "Yukata", which is a traditional Japanese cloth you will put on after having a bath, and just comfortably loose, and mostly easy to walk around in the Spa institusion.
Masa
Japan
