you could try just replacing the keyboard. That shouldn't cost much. Check ebay for matching keyboard to that model.
As far as the keys that stopped working - I don't think there is any repairing you can do. They might come back and go again - or they might just stay dead forever. Also, other keys could start acting up as well.
I agree with all the comments here. Take out the battery, discharge the power button, take out the keyboard, open up the bottom cover, and let it air dry for a solid 3 days! People often get impatient and they want to turn everything on too soon. Just for future reference - if anything electronic gets liquids spilled on it, the best thing is to follow the above steps and be patient to let it dry out completely. After three days (some people say just 2 days), try powering it again.