I've heard the nike boots fit a little more narrow than other boots, but I don't have any experience with them. I bet a 7 in the nike would fit. It sounds like your last boots were too big. Make sure that when you try them on that your toes are touching the front of the boot. You don't want them crammed in the front, but they should at least be touching. And remember that they will pack out a bit, so think about that too.