Brushcutters

I have a wheeled brush trimmer, model HU625hwt, and I'm having an issue finding a part for it. The trimmer rolled out of the back of my truck as i was moving my truck to the shop and broke this plastic piece on the axle. I found my trimmers parts manual online, but i'm just not seeing that specific piece? Everything else seems to be fine and intact so i just need to replace this once piece to get it back going again. Any help would be greatly appreciated. I provided a link to the parts manual and a picture of the damaged wheel trimmer. Thanks again.