Go to your local dealer and get kit B95299. It has a bearing , shaft , flanges, and hardware that replace the wood block. The shaft slips inside your worn auger tube and supports it that way.
My augers were the same way. I had a machine shop make me some stub shafts that fit inside the pipe and welded them on. I had to cut off some of the pipe on the auger. This was much cheaper than the dealer kit with the bearing.
I cut some electrical conduit (cant remember what size )that would fit perfectly over the worn shafts ends and tack welded them on. it lasted for years. it only takes about an inch or so, and it can be done under the combine in a few minutes. If some are not worn enough to slide it over just let them keep wearing until the conduit fits.
Wrong part number on my previous post. B95299 is the kit for the rear brg on the auger. The front kit to replace the wooden block is B95754 with an approx price of $64.