Im getting a new washer/dryer soon, so i decided shut my gate valves and disconnect hoses. The cold water valve was stuck but i got it closed..the hot water valve shuts..but drips, and i attached a photo. The valve looks odd, not the typical nut like the others ive seen. It seems big. Can I just loosen that and pull the body out, and can i just buy a new body to slip back in...id rather not repack since its pretty old. What would a plumber charge for replacing?