My guess that this was taken in 1955.
You may be right Howard as that was the year "Rebel Without a Cause" was released.
But the illustration has so many iconic items - the movie we just referenced, a poodle skirt, the letterman sweater, the two-tone car - that it feels to me like a modern illustration intended to look like it's from the '50s.
Also, the artist's style, while I can't put my finger on why, doesn't feel original to the '50s to me. That just my guess.