As I no longer own a wee I have for sale a Calsci screen. It will fit K4 to K8 Vees and up to L0 wees. There a few minor marks on it but in use they are barely noticeable. This is a fair bit taller and wider than the stock screen as you can see from the pics. Have a look on the Calsci web site for more info on why they think these screens are the dog's doodahs. Looking for £40 collected or £45 posted to mainland UK, excluding the highlands etc etc...
Edit: Just checked online and priced new these screens cost approximately £130 plus shipping from the US of A.