I am pretty sure that your engine and mine are almost clones, so it is with a certain amount of confidence that I can say that the hose you are looking for is actually a metal tube, that slips into the lower metal tube that is still attached to your engine. Btw, my lower part of the tube has play in it too, and I think that I would need E.T.'s fingers to get to that silly little nut that is between the bracket and the engine.
As far as the name goes, I think its just called an oil drain tube.
03/83 300D 184k
07/73 280 160k