I have seen a few specimens with 399,xxxkms but none have topped the 400km barrier. One was the old Citroen 2CV '54 that came with an eye-popping 199pp.
JaywalkerNever seen over 300k myself, but also have never specifically looked out for them.
I read an article yesterday about a guy who has done almost 3 million miles in his volvo in real life. The car's still going strong!
http://www.bbc.co.uk/news/world-us-canada-18803064
http://www.canada.com/cars/Retired+York+school+teacher+nears+millionth+mile+beloved+Volvo/6921068/story.html