You can find some information you need on their website
http://www.karenwalker.com/
London
b-Store 6 Conduit Street London W1S 2XE +44 207 4996628
Hoxton Boutique 2 Hoxton Street, London N1 6NG +44 207 6842083
Kokon To-Zai 57 Greek Street, London W1V 5LR
York
Paper Doll 39 Greek Street, London W1D 3 DX +44 207434 1316
Lincoln
Threads Unit 10, The Stonebow Centre, Silver Street, Lincoln LN210Y +44 1522528873