The 4 of the date definitely looks like doubling of the vertical bar. The 9 took a big hit but the 6 looks pretty strange... I did not see a match online but there are a lot of ddo's for this year I beleive. The East side of the bust looks doubled too.
It is very extreme, and you are probably right. The thing that bugs me is Wexler's site lists 43 doubled die 1964D cents, with pictures of 2..... Coneca lists some but again no pictures. How would one go about attributing a coin with no pictures available?
