No, I would just say grab some sheet styrene at your LHS and build it up and sand to the desired shape. It would be a little tedious, but if you took a bunch of flat "donuts" and sandwiched them together, then ground it down a bit with a motor tool, you could get really close and then use some sanding sticks to get your final shape. From there, just use some thin styrene or cut brass sheet for the remainder.
Groot