42" Snowthrower

I'm working on a 42" Snowthrower, and the auger is belt drive. Under the black cover on the side of the housing is a large auger drive pulley, an idler, a drive pulley, and a belt. I took the cover off to see the condition of the belt and I noticed that the large pulley is warped. It wobbles when the auger is spun. Not just a small wobble either. I'd say it travels 3/8" to 1/2" either direction of center during one revolution. It's so bad that it cut a groove/hole in the side of the black plastic cover. The pulley in question is part # 18 in the diagram below.
My question is, since this is a $50 part ($75 from mother Deere), is there any way to straighten a pulley or am I out of luck?. I'd let it go but from the look of it the belt will wear fast in it's present state. I think the unit must have taken a hit to that side at some point to do this, or maybe the auger hit something and the pulley took the punishment because it's in the drive train.