Originally Posted by Tullamore
There's gotta be scrapyard with buses you can pull em off of. Or you could always make a mold and then make your own out body filler or fiberglass.
Hey, that was my idea, too!
I originally suggested that he make a female mold out of plaster of Paris, and then line it with fiber glass and use a male plug (from the back side) made out of modelling clay to press the fiberglass down into the female mold.
Now that I think about it and look at the part more, your idea about using Bondo seems good, too.
Make the female mold, fill it with Bondo, lay some fiberglass on the back of the Bond in the mold, and put a big weight on it to hold it until the resin sets. The only place you really need the strength of fiberglass in a piece like this is in the flange area.
It might be a good idea to push some fiberglass down into the Bondo in the female mold just to make it harder to separate the Bondo from the fiberglass if the piece should flex any.