I was trying to find bearings for a piece of equipment (not a bike) as the manufacturer was out of stock. Went to a bearing wholesaler and they had that dimension bearing ranging from about five bucks to nearly fourty.
Chris King is the poobah of headsets. I have only seen one damaged ever and the guy pressure washed his bike at the car wash after every ride. The bushings in the fork had eaten thru the stanchions. If you are ever in Raleigh come by and look at them, they are on display.