I too live in VA, and I'd highly suggest against it unless you were actively in the woods out doing something legitimate. I live in Hampton Roads where we have an active open carry firearms group so it is not unusual to see someone in Walmart with an open carried SIG 220 or the like in a paddle holster. It's not illegal, but it's asking for trouble in my opinion and it's only a matter of time until someone calls 911 and says that there is a guy with a gun in Walmart.
I'm assuming you want some type of "hard use" knife, but there are so many great folders that will cause you much less headache. In my opinion, the less you deal with LEOs the better off you will be. You may be lawful and so forth, but unfortunately you may have to go convince a judge and that isn't going to be a pleasant experience.
Bottom line, there's just not many good reasons to have a K-BAR strapped to your hip in this day and age. If you have a good reason, then I'd make sure you have all your other stuff in order.