I hear ya, I have size 11 everything is uggo in the stores in that size, I just buy online.
And wowzah 5'3 with 10.5, that's craz lol
I'm around 6'0 so having big feet come with that.
Literally just pouring the coffee over ice, maybe let it cool down more or add more ice, but yeah, super simple, and well yeah, adding whatever you like in your coffee.
Ah, I love my iced mochas from Bucks, basically my go to.