Was it a loose capsule only? How long was it in water? Clean water? Omni or directional?
Omnis are usually sealed reasonably well front and back, but may have a small air vent. B&K once showed 4006 mics stirring a glass of water. Directional will have several acoustic vents in the back allowing more water in.
All you can do is try to gently dry it. I have doubts about rice, but warmth and silica dessicant should be fine. I might gently shake it occasionally while drying. At worse, you'll have to send it in for disassembly, drying and cleaning, especially if the water wasn't clean. That might really be best anyway, even clean water could cause some corrosion or leave deposits.
I've disassemble Rode NT5 and Neumann KM84 capsules, and they aren't that complicated.