kevlar .014 i believe buy it on ebay or at hobby lobby in sheets. or already cut from callers supply. 10mm, 12mm amd 14mm are the most common you will find I do have some that measures 7mm that I have used for predator calls. 14mm for goose and 10mm for duck and I do make some double reed calls where I use 10mm and 12mm
Turn my own, any wood you want you can use, I like cocobola, and you need mandrels the right size for turning ur barrel and one for your insert, a toneboard jig. I like to use pin mandrels. I finish mine with teak oil.