I have a 2wd 2001 Silverado and I noticed on the inside of the steering knuckle that the dust cover is missing and the bearing is exposed to the elements of the weather. I have been everywhere looking for one and it's not the the chevy parts book. the dealer says you have to buy the entire bearing assembly $385. Been to jumk yards and they too will only sell me the entire knuckle @ $100. Can anybody help? thanks