Just to conclude my topics I found hevi-shot buckshot and 10ga brass hulls.
ballistic products has a small amouint of the buckshot for sale at $14 per lb, and are not sure if they will stock it fully yet.
Ballard rifles sold the case part of their business to Rocky Mountain Cartridge, who makes lathe turned brass including the real big gauges.
Thanks for the help. Great forum!
Karl.