It looks more like it's patterned on this style of stack as used here:
These were associated with the west coast, most particularly during the 1880's and 1890's. I agree 463 looks better with just the headlight, however Hollywood maintains this strange perception that "old timey" locomotives always have to have a big fat smokestack--which of course is silly. I suppose that misconception occurs because movie folks are typically artists, not historians.
It's possible they opted for the stevens-style dummy stack because of the size of the inside pipe. 19th century diamond stacks (as in your photographs) have a certain proportion; the increased diameter exhaust pipe used by more modern locomotives precludes a small dummy stack from having the same proportion when fit (see: the ugly diamond stacks sometimes used on the K-28's).