BST Wheel Spacer... Can someone measure this for me?

[Dragsterhund]

So I've got a set of BST wheels, and I'm missing a spacer... it's part #7 on this drawing (Part number: Ducati Monster S4 CRW Outer Sprocket Spacer ver C14010-8000-19-004-C ). It'll take 4-6 weeks to get the part from the factory, so I was wondering if anyone here who has that spacer could measure it so I can machine one myself.

[Speeddog]

My deductions from what that part needs to do, what it fits, and that drawing.

I do not have said part, so this drawing is approximate.