the impul kit with wide arches etc is excellent! but also cost a bomb.
then theres the prospec kit which isnt all that, but with a good spray job can look excellent.
the wald kit is one of the best k11 kits about but also quite pricey!
theres a wald look a like kit on eBay for roughly £350.
the build quality isnt so great though.
or you can widearch rally style kit from rally people in UK. which looks awesome. Will need to play around with spacers etc though!
If not the citroen saxo kits can be quite easily modified and wrapped around a k11.