Lost Devon Rex: Charcoal Gray & Shy - Help!

Male Devon Rex cat, 6 years old, with very short and slightly curled solid charcoal gray fur, average build, about 13 lbs., has a long and thin tail, and gold-yellow eyes. He has no tags or collar, he has been vaccinated for rabies,. He is very skittish and shy around strangers, but not at all aggressive. He slipped out of the house during a gathering where people were coming and going and the door was open long enough for him to get out. He is a very good hider. He does not like being outside at all and has always been a strictly indoor cat.