In reply to Brian Pollock:
Hanwag do some wide versions which they call ‘bunion fit’. I had some but suffered heel lift with them. Very difficult to try before you buy.
Im currently using Salewa which are moderately wide at the front but still snug at the heel. More widely stocked. As a word of warning on some models the rear crampon bail lug is quite narrow so worth checking crampon compatibility, and also their sole units wear down relative quickly on all models. I have the Salewa Vultur Evo GTX which are fine as a general mountaineering boot (solid traditional stiff B2), and robust upper. Their lighter offerings Crow and Repace are billed as B2 with a heel clip, but are actually relatively flexible I regard as B1, and every pair I have had leaked virtually from day one.
I have never tried Salewas full B3’s.