64-67 Hemis lacked VIN#'s.

Speaking on 66/67 Street Hemis you would see the year code, cubic inches, assembly date, build sequence, and any other symbols denoting special opperations (OS bores, etc.) on the machined pad opposite of the distributor.

For instance a 66 Hemi engine pad might look like this:

BH 426 HP

10 14 07

Breaks down as:

B = 1966 model year install
H = Hemi Engine
426 = Cubic inches
HP = High Performance
10 = October (1965)
14 = 14th day
07 = 7th engine assembled that shift

*A 65 or 66 casting date block from a different car COULD be considered technically correct for your 66 car, but only if the block is stamped BH 426, and only if the assembly date is close to your cars Scheduled Production Date (a week or so before, or in some less common cases a few days after the date are the norm) so finding a "correct" engine with the right date and stampings is more difficult than most people think.

If you'd like to know more about your engine you'll need to post more info. The partial VIN stamping will not tell you what exact model it came from (only the body style as Barry pointed out) only where and when it was build, and what model year it may have been installed in. Most blocks cast in mid 1969 ended up in 1970 or 1971 model year cars. Look for more stampings on the oil pan rail extension and the upper pad opposite the distributor, post pics of what you find for more clues as to what you have.