The mounting brackets on Eurovan Camper luggage racks can rust significantly over time.
There is a good description of repairing the luggage rack mounting brackets here.
Another good source of information is here.
A new luggage rack can be ordered from Lichtsinn. In Winnnebago parts diagrams the part number is 1130770101A. The description is EACAP-ROOF,POP TOP,FRT VW WHT.