Unfortunately a new prebent line is unavailable because it's discontinued. You should be able to pull a complete brake line from a wrecked Dart at a self serve you pull junkyard. If you want to bend your own line, use nickel-copper, not steel. It will never rust and is just a little softer so it's fairly easy to shape. The flare at the end of the line can be made with a hydraulic flare tool. The tube nuts can be purchased new at an auto parts store or reuse the originals. You can also make a small section and use a brake line union. There should be you tube videos if you search.