When you're looking at the sizes of footwear on REI.com, you are looking at the USA size. So if you're looking for the same size as the pair you currently have, you'll want to go with a size 9.
It does look like we have a wide size 9 available in the Salomon X Ultra Mid GTX Hiking Boots. They're a great boot, if you've enjoyed your Salomon X Ultra shoes, you'll very likely enjoy the boot version as well!
Hopefully this helps!
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