Columbia 6" Twentieth Century Cylinders

For many years I have been trying to complete the entire run of Columbia 20th Century 6" cylinders and I am down to only a few I still need. Will trade other 20th Century cylinders plus cash or top cash price paid or other rare cylinders or parts or reproducers for trade for those I need. I would appreciate hearing from any collectors that have any of these cylinders and the catalog number of the cylnders you have. Thanks, Larry

hawescpa@aol.com