Ray already is a nickname, but you could call him Ray-Ray.
Famous people named Ray:
Actors Ray Romano, Ray Liotta, and Ray Milland; musicians Ray Charles, Ray Toro, and Stevie Ray Vaughn; author Ray Bradbury; football players Ray Lewis, Ray Edwards, and Ray Rice.
The world knows him as the scarecrow from The Wizard of Oz, but the actor's real name was Ray Bolger.
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