Size 10 Narrow fit women's occasion shoes in the UK
Amazon UK
You can get great deals on large size shoes at Amazon with a bit of patience. There's usually a good choice up to size 10 UK. Their own Amazon Essentials range now goes up to size 11 UK, with fashionable styles at great prices. The women's shoes department goes right up to 14 UK, although many of the largest sizes will either be Chinese brands or unisex. There's free returns within the UK for most shoes sold/fulfilled by Amazon & if you've got Prime, you can even try before you buy.
Margaux, USA
Modern beautiful shoes, sandals & boots in 3 widths (narrow, medium & wide) up to size 45 eu (13.5 us) including half sizes. Free US shipping & returns. Also ships to Canada, UK, Europe, Australia, New Zealand, Japan and Brazil with all taxes included at checkout. Free 15 minute fit advice phone calls. Made to order custom wedding shoes also available. Shop in person in at their Bleecker St NYC flagship store.