Cheers for the replies guys. I've got a shiney, seven iron next my door, just waiting for anybody that decides they want a free splitter, bit of trim etc.
I just spoke to my insurance company about my renewel, and managed to knock £55 off the price (+ got protected no claims into the deal for £520), so that saving will pay for the new trims (£21.07 each + VAT from VW). This time round I will be riveting the back cap on, which otherwise just snaps off and allows these little sh*ts to slide the trim off without the aid of any tools!