I wear these weird American boots: http://www.whitesboots.com/
I wear these weird American boots: http://www.whitesboots.com/
Skate shoes generally have hard soles too, and minimal padding. You could even take out the insole.
Since he's a rapidly growing boy, I'm reluctant to get weightlifting shoes for him until I'm sure he's into lifting. H doeshave hiking boots, but they're as padded as sneakers. However, 30lbs on his back probably won't compress his soles much.
Does he have any dress shoes? Those work better than squish or barefoot.
I can't tell much about his shoes from this picture. But there is a picture of Starr in SSS lifting in his pennyloafers. Forgot his shoes that Saturday.
The TUBOW (terribly useful block of wood, 2x4 cut to size from floor to a couple inches higher than the kneecap) will stop the knees being forward in a short period of time. Its in the book and really does work, you can't cheat it and if you set it two inches in front of your toes your knees will not go two inches in front of your toes without knocking it over. Try it you'll like it.