Replacement glass for Parkinson Cowan grill door (UK)?

Just wondering if anyone knows where I can purchase the glass from my Parkinson Cowan cooker glass door in the UK. My husband tried to take the door off and dropped it and the glass has smashed. The model is sg553wn its 18 months old. Do I have to buy a whole new door for it or can I get away with just buying the glass? Thanks ever so much.