Not much we can tell from such a low-resolution sample.
It is some form of Courier, which has been around since 1955.
If a typeface didn’t exist at the time a document using it was purportedly created, then that typeface’s age could be used to disprove the date of the document. That is not the case here.
You’ll need to find another means of authenticating the date (maybe the notary seals?).