Here's one I did. I didn't do the final step of adding in the front.
Some steps I left off of my earlier example.
- use the shift key to constrain your angles to 45 and 90.
- use the scisor tool to cut the wedge out of the circle.
- use the object, path, join command to join the endpoints of the line and the arc.
- with the gradient tool, look at the pallet to change the angle (-45 degrees in my example)
It only took about 10 minutes. After you have one, you can scale it to whatever length and width you need,
You will need to make another if you have a different angle (like an angled CP).
Remember that sections through circles are *always* elipses in persepctive (not ovals or any other shapes) and you won't go wrong.