AN Power Steering Hose
It's not the threads so much as the type of fitting. Some of the older GM boxes used a 3/8 tube inverted flare fitting, but with the nut size that would normally be found on 7/16 tube, AKA larger than normal thread. Many of these fittings (don't know what they are called) look somewhat like inverted flare, but they have a protrusion on the end for an o-ring seal.
"Used to be weatherhead" hydraulic fittings (and other brands now) make/ made some interesting fittings for general repair.
This is one I picked out of my memory, 06U-755, it's a heavy duty compression fitting X 3/8 crimp on hydraulic (2 braid) hose end. You cut off your bad hose, assuming enough of the steel tube end is OK and this clamps onto the steel tube
This one I found from an Aeroquip side, weatherhead used to make some of these for power steering, either straight, 90, or 45 bend This is the forementioned inverted flare