JS, why not make them yourself. You can do it for about 1/3 of what it will cost you to buy. It really isn't that hard to do. If you check out my website,
http://MLRDsitributing.com you will see that we sell reloadable shells both screw apart and once fired commercial aluminum shells. Plus we offer cardboard disk and tubes both plain and fused. If you have any questions just let me know!
Mark