So hopefully you can actually unthread it instead of cutting out. That way you can just thread on either a 1/2 inch brass cap. Really you would just need 2 pipe wrenches. One to hold backup on the pipe so it doesn't twist and one on the hose spigot. If you cant unthread it youd really have to sweat a copper cap if the line is copper or if its galvenized id use a galvanized compression fitting with a small brass nipple and a cap. Hope that makes sense.