Found it on several pages of the 1963 Mopar Parts Catalog (published January 1964).
It is the Fender Side Name Plate for the '63 Dodge 330 (2dr, 4dr and wagon) and the 440 (2dr, 4dr and wagon). The nuts that hold that on are part number 152-260.
BTW... where's a time machine...
I just looked in a Mopar Collision Parts List book that was published in 1963, those emblems sold for the unbelievable price of $1.50 each.
