I couldn't say without looking. It's possible but most likely it's just stuck from dried oil and sitting. My experience with the two I have that have broken gears is one the gear disintegrated when it let go so the top half turns freely and the bottom doesn't move. The other one has a cracked hook drive gear and that one will turn but hangs up at the crack.
That machine looks old enough I'm guessing it's all metal inside so the chances of a broken gear are smaller.
Rodney