can't answer that because I dont have alpinestars.
I wear a "large" size 12 meaning its tight in most 12 shoes and boots so most of the time I buy 13 and put an insole for better arch support.
Width wise I am fairly wide: for example in shoes: Pumas are too narrow so are most brands except addidas
For width i found Gaernes to be perfect width wise.
I hope some of these comps might help.
when I go back to the store i'll see if they have alpinstars in 13 so I can give u an accurate comp.