Having owned a Brava and worked on Andy's Marea, I'd be pretty confident the interior from a Marea would fit fine.
Although the shape of the rear doors are different, the bottom part (where the door card is) is the same. Front seats don't move on the Brava so Marea ones will be fine.
Longest Serving BOO Member
Stilo (3dr): Mar 06 1.4 16V Active Sport / 33,500 miles
Coupe: Feb 97 20V N/A / 137,500 miles