My local auto parts stores do no not reference NGK plugs on their computers by the size/heat range... If I ask for NGK B6HS or NGK BR6HS they tell me they don't have it. If I ask for NGK 7534 or NGK 3922 they ask, "how many do you want?"
NGK 7534 = B6HS and NGK 3922 = NGK BR6HS