I believe the little th was on some balls but not all. My old Brother (which is a disk system) is the same way...it is on some but not all. You want to look at an IBM KEYBOARD.
Honestly, if they wanted to forge a document, wouldn't you put a little more thought into it? If this turns out to be forged somebody should be given a ticket for stupidity. There are lots and lots of free "typewriter" fonts on the web designed to look like old monospace typewriters and even to look like old teletype machines, why would you be so foolish as to not use one of those?