I have not tied tubes for the salt, however I have tied steelhead patterns on brass tubes. I made my own tube/liner set-up with hobby store brass tubing and plastic tubing to fit inside. I flared the plastic tubing and slid it inside the brass and measured it for length and cut it, then I super glued it inside the brass. This is not really a hassle once you get the materials and it is a heck of lot cheaper than the store bought versions.
Tight lines - tyler.