For both of you, from another thick calf gal... they can be stretched, anyone who does boot repair/sole repair can stretch most boot shafts (unless they are tightly and intricately stitched).
all of my boots leave the store and go to my boot guy for a couple weeks for a good stretch and they never “shrink” but you can buy boot trees to keep the shape when you do not wear them daily or just general upkeep.