British high street chain Next has over 400 of their own shoes & boots range in size 9 uk (43 eu) online, although they may be rare in store. They also have footwear in sizes 10-12 UK from other brands including Yours, LTS & various sports brands (NB LTS run small, so go up a UK size). Their website navigation is not great on desktop, so I've linked directly to the Next brand size 9s as a starting point. But if you click on view more/all under the size filter list on the left, you can choose other sizes.
Huge range of women's shoes in European sizes 42-46 (including some half sizes), with some unisex styles beyond that. Mainly standard or wide fit footwear, with a few narrow width options. All shoe types covered including bridal, slippers and rain boots (wellies). Schuhplus have several stores in Germany and ship worldwide. Website in German but there's a google translate widget at the top that works well.
Specialist large size shoe store in Quebec also selling online to Canada ($10 flat rate shipping) with a wide range of women's shoes in sizes 10 to 15 US, with selected fantasy styles up to size 17 US. Large selection of brands and styles. They even do rain boots, slippers and socks. They are happy to advise on the right size for each style if you send them your foot measurements before ordering or during checkout. You can also visit their shop in Rue St-Hubert, Montreal. Website is in french.
Famous Irish catalogue shopping website with hundreds of size 9 shoes. Lots of brands including Cushion Walk, JD Williams, Simply Be & Hotter. Particularly good for wide fit shoes with wide (E), extra wide (EEE) & even a few ultra wide (5E) styles as well as standard fit shoes. €5 delivery but there's free returns.
Gina collates wide fit & extra wide shoes from lots of UK stores, including special large size lists for sizes 9-11 uk. She also lists bunion friendly shoes & wide socks & tights. Subscribe to her newsletter to get new shoes every 2 weeks.
DB Shoes manufacture wide fit footwear in widths E to 8E with all shoes made in the UK.
Most styles are available up to size 9 UK, with a few styles available up to 12 UK. Due to the wide nature, some may be able to go down a size from their usual size. See the detailed fitting info on the DB website including a downloadable fit tool you can print out & use at home.
There is a large number of shoes, boots & slipper styles. Most styles are everyday comfort shoes, especially good for those with health issues affecting their feet. A limited range of dress shoes are also available.
Flat rate shipping available worldwide, but this is expensive outside the UK. Free returns within the UK but international returns are at your own expense.