Visiting London, Looking to Buy High Quality Leather Sneakers

Going to London for a month beginning in August and am going to be daily driving my margiela gats. Looking to purchase another pair of high quality leather sneakers. I've heard crown northampton is really good but they're made to order and I'm mainly looking to purchase in person. My Budget is around 600-700 GBP so let me know what you guys suggest. Thank you!