I have a similar problem. I have just south of 4000 #57's. I recently was able to get 200 primed hulls off of GB and had another 100 cases. I'm presently loading them now for my target shooting and starting to make a dent in them. One fella I talked to from this board suggested to cut short pieces of plastic straw and put these over the primer and seat them in a standard 209 case. There are diffrent size straws so you have to get the right ones. I tried it and it does work but is very slow. I would load these for hunting loads since not that many are required but I shoot alot of targets and with components a bit hard to get now I went the old Remington hull route. Another thing you can try is to glue them in a standard case with RTV silicone. A little smear around the primer pocket should do it and you can let these hulls fly.
