Common Words:
* key
* grey (American English)
* gray (British English)
* they
* whey
* sleigh
* obey
* convey
* survey
* money
* honey
* monkey
Less Common Words:
* abey (to cease or stop)
* bley (a type of bird)
* dey (an old-fashioned word for "day")
* fey (unusually sensitive or inspired)
* gey (Scottish for "very" or "quite")
* hey (used to attract attention)
* kley (a type of clay)
* ley (a meadow or pasture)
* prey (an animal hunted by another)
* rey (a type of king)
* sey (a type of sea)
* toney (stylish or elegant)
* wey (an old unit of weight)
Words from other languages:
* boney (French, meaning "good")
* chevey (French, meaning "goat")
* ckey (German, meaning "key")
This is not an exhaustive list, but it gives you a good starting point. Remember that some words with "ey" might have a different pronunciation.