I can remeasure mine
The dimensions are probably in the archives as I gave them not to long ago, for someone else. I can remeasure though if you cant find them, If I was looking for a boom Id even consider making one out of wood. It would work , and you could even make it hollow inside for lightness. . Just a thought. Let me know if you still need a measurement. I dont remember off hand what it was. It might be under the title gooseneck too as the person wanted to know about that as well.