As per title, does anyone know where I might obtain a set of valve caps, top and bottom; and buttons from a vintage Besson New Standard euphonium? Colour is irrelevant as theyd be refinished anyway.

I much prefer them to the milled buttons on my Globe, and having swapped them on British euphs previously know that they will fit.

Im asking as far and as wide as I can because they seem to be in extraordinarily short supply.

Thanks for your help!