This is my day for strange posts.

Salty, that gear/shaft is actually within the range of normal variation for a brand-new part. Incredible but true.
Here is how to tell if you can use it: look at the gear backlash all around the gear. If you can set the backlash so that the gear does not bind at any point and is not over 0.004 inch at the loosest point, and the _top_ of the shaft where the head mounts is running true, then go ahead and use it, at least until you crash and really bend it.
It looks to me like the pinion is making good contact almost all the way around, so if the backlash can be set within limits you should be fine.