Yeah... replacing only the blown section just pushes the problem down the line. Literally. I've replaced copper tube with marine hydraulic steering hose... it's black with a ships wheel logo about every six inches or so. I think it's Wagner. Also, re-routing the new line to be accessible under the cockpit as opposed to the original run which usually is not.
While it's disconnected and drained... a good time to rebuild the helm pump, auto pilot, and hydraulic cylinder.