Bought some cream from a caravan dealer when we were tuggers. Can't remember what it was called but it was a small yellow tube and it worked on the faint scratches you get when you use a gritty sponge (it was the wife, honest). Don't know if it would work on yours but it's worth a try.
Stock Code Description
5060012761349 Fenwick Windowize scratch remover
Part No. Price Stocked Item?
358140 was £5.99 Yes
More Details... now £5.69 inclusive of VAT and 5% online discount
Fenwick's windowize has been developed as a result of customers requests, for a simple but effective product to remove scratches from Acrylic / Plastic windows.
This handy 50ml tube provides enough product to tackle the windows on a caravan, motorhome or boat, a little goes along way.
When applied by hand, Windowize will remove scuff marks caused by trees as well as minor scratches caused by dirt, grit and manufacturing processes.