May be worth having a look at this week's Grazia ? They have a Karen Millen pair for £300 which look like a pretty close copy though they have a heel rather than a wedge. They also have an £18 burgundy fringed pair from Primark although they look nothing like the Isabel Marant boots and again have a heel. I cannot imagine how Primark manage to produce a pair of knee boots for £18. DP has already sent Grazia to recycling so cannot give you precise details !