That appears to be a mid-60s inline headstock on a 15-fret neck. This configuration was often referred to as a "shorthorn" model bass.
The inline tuner configuration was being used at the same time that Dano was cranking out guitars under the Coral brand, like the Vinnie Bell electric sitar. The interesting thing about this particular model is the older body style mated to the newer neck. I'd estimate a build date of around 1966-67.