That's a new one for me John, a bit too morbid to have been a big hit in '73 IMHO, and looking at the ARSA database the only radio station that gave it a chart listing was XEG in Monterey, Mexico (which I understand was one of those night-time "border-blaster" stations that could be heard across large parts of the USA at night ... a bit like a North American version of Radio Luxembourg).
However XEG did list it as high as #13 on October 22nd 1973, and had it on their station chart for at least eight weeks so they must have given it plenty of spins ...
http://las-solanas.com/arsa/chart_view.php?sv=182119I wonder if it is available on CD as it's just gone on my "wants list".

Roger