don't know the answer but i've been using an old Zeus beater for commuting and it's crankset/chainrings and the twin bolt seatpost have the world logo.
i can only guess the bike (durifort tubing frame for 27" wheels) might be of 1977 judging by the last 2 digits of the serial number.
only a guess... is that possible?
It might not be new to you all but I only just found the blog Recordando bicicletas Zeus. It brings a lot of information together, for example scans of all(?) the catalogs: 101 (1970), 102 (1973-74), 103 (1977), 104 (1980) and 105 (1984).