dido that, after last contact i found examples of breathers like those described by NumberDummy also saw a couple air pump systems as well. made me go dig up my breather and manifold and check them it it's starting to sound like mine have been some home made get up prior to me owning the van. I'm a bit goofed because my wet air cleaner has no fittings on it. Yellow paint on the engine block would suggest the engine had been replaced at some point. I'm not sure but I think the 240 first came out in '65 perhaps a lesser emission standard? The image for the molded line to the air cleaner looked identical to the one my '75 300 breather. My guess that part didn't change until fuel injection. That part might still be out there. NumberDummy laid a few sources on me when I needed a heater core. (they'er on one of the messages from about a year back) If a part # could be had it "might" still available O.E.M. I doubt napa or advance would have it. Roll stock will work but not be as finished an appearance. the mold-a-hose coil over may be available that small. or lay a stiff steel rod inside and shape it.
old antenna works well, real stiff and generally stainless steel yet small enough not to restrict flow too much.