GM Partial Code stamps are found on most ,if not all, early Chevy V8s. Typically the first set of numbers from left to right on the engine pad.
The Engine code stamps are the larger stamps on the same pad ,To completely stamp the engine both engine code and partial stamps are needed. (see other listing, GM engine stamp | Engine code)
This stamp will be a single stamp, with the same font and numbers that you need. Please take a photo before you take your engine to the machine shop so we can ensure accuracy.
Usually 7 characters long.