Hi mate, welcome to the forum.
In my opinion it boils down to cost, regarding the bonnet. You'll get what you pay for. Ideally you'd get it resprayed and the paint code taken first with a spectrometer. Otherwise, you might get lucky and find a good bonnet that matches your paint, but I can imagine that might entail a fair bit of 'approximation' if you know what I mean. My bonnet's the same, and it's red... so they show up really obviously. I might just touch them up at some point, then make a decision depending on whether it looks ok or if it still looks crap. I don't think mine are rusting (yet) so I might get away with it.
As for the wings, you shouldn't have too much trouble getting them replaced by VW. There's a big thread somewhere with page after page of info on people's dealings with dealers, from good to bad. I was lucky, and got mine replaced without any hassle. I used the Seat dealer in Hillsborough. If you're anywhere nearby I'd try them. You could ask them how much they'd want for doing the bonnet at the same time, but it won't be cheap. It's maybe an idea to get the wings done first and then tackle the bonnet (or get the bonnet done at the same time if it's not too dear) to make sure it matches the wings. You can get the wings blown into the doors, but again that'll cost. I took a punt and didn't bother with getting them blown in. It turned out to be a good match.
