So the 4 little bits you mentioned won't fit as they're off a 5dr You need all 6 trim pieces = 2x door, 2x wing, 2x rear quarter
Mine are colour coded but you get the idea..
I had no rust behind my trims but there was a nice line deep in the paint where the trims had being sitting for years! But you can get new rivets from vw for 20p each