That's what mine looked like, except the gear was in 2 pieces.

Dang it Apex I should have packed the worm gear assembly in that box too. If the worm gear is wrong it will chew up that replacement gear. Let me know if you want it.

Worm gear was in the box, no worries!

I need to do the shifter adjustment as well on the bike, so will do the worm gear at the same time.

I meant part 37 in the diagram. I thought that was the worm gear.

It was in the bag with the parts, with the plastic drive gear! All there.

Dang I’m an idiot, I guess it was huh?

Nope!!

So, pulled the pump and clutch cover. I needed to make a shifter adjustment, so pulling the cover to swap the worm gear was the proverbial 2 birds 1 stone. Also got to change the worm gear shaft oil seal since the cover was off. Cover back on, proceeded to remove the oil pump cap and change the worm gear's driven gear that was damaged.

Yes, I lost one of the tiny sprag pins, it just flew away! I have a really nasty spare oil pump, shaft totally seized from the $100 AT1 I'm restoring, so popped the cap and got a spare pin, and successfully re-assembled the driven gear & sprag. On looking at the now three driven gears, one from Midlife in the pump, the damaged gear taken out, and the driven gear from the nasty pump removed to get a sprag pin, the damaged gear looked noticeable smaller. I counted teeth:
- Gear from Midlife (off a DT1)- 55 teeth.
- Gear from Nasty Oil Pump off an AT1- 55 teeth.
- Damaged gear removed from my DT1 oil pump- 40 teeth.

Yes, I recounted, twice. I have no idea if the pump on my DT1 is the one it was born with, but, 15 teeth difference?
And I noticed in the "Oil Pumps" thread user Kwzl1 started today for his DT175, the driven gear in his picture looks damaged like mine. And he knows the shaft was seized on his pump.

My non-engineer, layman's assumption is gear on my bike was damaged by the pump shaft being seized or very difficult to turn when I fired up my bike last Spring. Can't be 100% sure...but a warning to others...remove the pump when firing up a long dormant Enduro!

Fire away...I'm just postulating.