Some products are copies (wheels in particular), others are genuine in Porsche boxes. I can't commetn on their bodykits, some of their spoilers are certainly glassfibre copies. If it looks too good value, its probably not genuine.
You could also try
www.jasmine-motorsport.co.uk - they have genuine GT3 bodykits for the 997, so no reason why they couldn't source somethign for the 987 too.