Looking at this it looks like you have 2 piece design in mind and that just won't work and look the same.? It would need to be much more robust at the spindle portion to allow inter locking joint to stop rotation.
This part needs much more work on design and strength because has robsk1 says it wouldn't last 5 mins under heavy breaking with these proportions.

I Also doubt anyone will give you a quote for an incomplete design thats flawed in such a major area given the nature of it's importance.? I certainly wouldn't.!