The teeth are showing years of wear but they would still work. If it's just spinning and not engaging your Bendix is probably bad. You could just replace it but it won't be long before you need a rebuilt starter also.
Pastor, Those starter drive teeth don't look good to me at all. I would replace the drive assembly.
But I have not read from anyone telling you to check the flywheel ring gear. If the ring gear has some teeth missing or badly damaged, most any starter might not engage to turn the engine over.
My advice would be to check the ring gear out completely, all the way around. If you find it bad, it can be replaced on your existing flywheel, by an automotive machine shop.
If, as you said, there are lots of sparks when the starter is running, you might need new brushes, and maybe need the armature commutator turned true again. Check the starter end bushings for slop too. It could be the armature is jumping around inside the starter housing causing the brushes to arc like that.
Thanks...the sparks came from the top post when I tapped my jumper cables to it. Nothing came out the back or anything. I'll inspect the ring gear(motor still in truck) by painting a tooth and turning it bit by bit and see if they are all there? I get a clear view in the starter housing. I was thinking the starter drive looked a little worn myself