Having trouble sourcing valve guides for a Courtois Euphonium. (Or even making succesful contact with a rep!). Its the 167R. I had it overhauled and silver plated recently but unfortunately the valves are a bit 'rattly' and can rotate a wee bit in the casing making me think a set of new valve guides are what is required. Have attempted to contact a courtois rep with no success, would really like to get this done before Birmingham... Any help/contact numbers would be much appreciated!