Whilst we have learnt' to keep an open mind, I have to agree with Steve.
Certainly looks to be a sandcast (l/H horn, etc), few bikes can be authenticated to be totally original by the time they reach 46 years old.
My moneys on a paint swap, or repaint, assuming of course the serial numbers check out. Would be inetresting to look in the gas tank - never seen a factory Gold wrinkle tank.
Chris