Hello E.,
We specifically need all the information that is stamped into the top of one of the engine rocker/valve covers. If the valve cover has been off, it could have been reinstalled upside down, so the numbers would be on the underside.
Can you see the gear on the top of the starter? If not, the top plastic fan shroud will have to be removed. They are pretty simple to take off.
If it has the black plastic/nylon gear, it may have split in half. I have that happen several times in recent years.
The individual gear can be replaced but it takes some skill and patience.