Try jackboots, they’ll suit youCustom boots (fuck Dan Posts and all the rest of the commercial crap) with a tall shaft and a good sheath behind the anklebone.
I have a pair of English hunt style boots (the ones that tie in front of the ankle) with a sheath in each but the handle sticks up and shows. That's not good for city work even under jeans. (which make it impossible to get to the knife anyway.)