Those numbers are not the actual "head" casting number. I believe they are often referred to as the "sand casting" number used as the base for the specific head casting to be made from.
The actual "head" casting number is located on the top surface of the head, drivers side near center of head just outward of the valve cover.
Below is a link (original source credit given to Tim's Trucks) from another Stovebolt thread that provides a great deal of pictures and info on where to locate engine block/cylinder head casting numbers, casting date codes and original serial number placement.http://www.1954advance-design.com/Web%20images/casting-code-photos/codes-ser-nums.html
Once you have all this information, there are other links (use the "Searching the Site" link in the forums left margin) that will help you identify what you actually have.
Let is know what you figure out.