Uffda, I will be having a willow tree cut down from my garden in a few weeks time. It is the upright one that has branches now slightly bending over. I am not sure whether it would be of interest or how much you might need, or if the wood should be dried (probably not) and what thicknesses you need.
I could cut branches before, for you or wait until nearer the end os Sept.
Let me know. Happy to help if it is any good.