Last winter I bought a pair of Clarks Fawley Hi fur-lined boots in nubuck, I think they were about 75 quid from Clarks website. They are possibly the most comfortable shoes I have ever owned, they are very warm (it gets a bit nippy round the ankles on a Vespa) and 100% waterproof. I wear them with a suit or with jeans and they don't look out of place with either.