1. not sure if you can... you could always trade one from gold... in gold there are lv. 45 missy's in the 2nd floor of mt. silver... hypnosis can't be taught to missy, it's an NYPC move.
2. evolve into gengar, give it destiny bond, mean look, fire punch, psychic... other options are hypnosis, confuse ray, spite, thunder, ice punch, and perish song + protect