I'm no expert in golfs but if they are anything like the mini the scuttle is part of the shell of the car and as such is not a panel that can be "replaced". With the mini no new original panels are available to fix this (It's a real common problem on them even the last year 2000 cars rot like hell around the screen). However many companies offer repair panels which can be welded in to replace the rotten metal that is removed.
Hope this kinda helps,
Nick