Might try wildcat auto wrecking sandy Oregon. A parts wanted add also can help but also careful for scammers. The trunk pieces are the ones everyone seems to be looking for.
I’d try the ACC radiator. I have a champion in my 65 Dart 273 and it needed mods to fit. Not difficult, doesn’t cool at all at idle. Does great while driving. I wouldn’t buy again.
Vintage Car and Truck Radiators
I believe they do fit, there is a thread. I believe it takes a cut down steering column and grind on the drivers side manifold some. Maybe a few shims on engine mounts.