Is starting to show signs of wear and tear with some scratching and discolouring.

Can anyone suggest a treatment?

Thanks

That is most likely fiberglass so superficial scratches can be buffed out or covered with fiberglass body treatments found in car section of Tesco or similar. Not much can be done for the discoloration other than some form of paint which would probably be even worse than just the discoloration. Perhaps one of the car detailing shops may be able to help.