The AIM is wrong with regards to the part number for D34. It should be 3945964 not 3945962.
And yes, that looks like it might be a later version of the mirror. Probably mid to late 1970's or so. The original 1969 version didn't have that lip, nor did it have "Chevrolet" written on it. It was just a flat piece of glass (see below). This mirror was also available as a service item (as well as dealer installed) and was P/N 993723, which changed to P/N 994521 in 1973, and was available until the late 1970's.
Ed