Lots of BB Parts

[GregOConnor]

I would think someone could fiberglass repair them for less but 350. per seems reasonable for vintage oem. . you would want fiberglass repair shop to have the bus so they maintain the shape for a refit. 5 years ago RobR of Canada spent a week replacing all the screws on my roof with new and larger diameter stainless. He dressed each one up with a sealant.

The cracks may be a result, for sure the rust is. water may be getting in under the part and not have a way to drain. when you refit it, may be a good idea to not calk all the way around and leave a low spot escape for trapped moisture. cracks may be caused by body movement or uneven expansion I think the part covers metal on one end and fiberglass front-cap on the other?