The 7.75 and narrow width complicate things. I'd start with the standard width 40.5 first. It may actually be perfect. If too short, 41 narrow may be the way to go. 41 standard will definitely be too big.
New Edward Green in a great DOAK shade and 82 last (Smoothie could use some better photos). 10D US. About $700 shipped. If I wasn't overloaded on oxfords, they'd be mine.