It is a HUGE time investment to make modern shoes.
You are right that leather soles are poor insulators. You could probably find dress shoes or cowboy
boots with all leather soles.
I have played around with modifying shoes, using copper rivets or fine copper wire. You can use the wire like
thread and sew it fairly easy into summer weight shoes or sandles.
"You must be the change you want to see in the world." "First they ignore you, then they laugh at you, then they fight you, then you win." --Mahatma Gandhi
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