Got a silver 172 spoiler and a standard black plastic spoiler on eBay at the moment
http://shop.ebay.co.uk/adamio2104/m.html?_nkw=&_armrs=1&_from=&_ipg=&_trksid=p4340
http://shop.ebay.co.uk/adamio2104/m.html?_nkw=&_armrs=1&_from=&_ipg=&_trksid=p4340