The previous Rover mowers were images from online the blue one is on ODK and Tyler has a link to that one.
I do have a MSAA 1978 Craftsman ,it's a different Base.
Tyler ,I do think you are right about the time line when the phone number changed ,It's just sometimes there are variables ,like did someone use up old stock (id plates) on this Craftsman model ,I do own a Red Magnet Rover and that has the old phone number but also have a 1981 Red Rover Ute with the newer phone number ,I'm just thinking it's a possibility that the blue Craftsman could have been built with old stock bases but newer engines ,just saying there is sometimes an overlap when old parts are used up with newer parts but this blue based Craftsman does look 1979 to 1980 from the evidence we have so the cowl or engine could have been swapped at some stage.
The safe bet would be to say it's a Rover Craftsman 1979 to 1980.
It's a long time ago that I had the Red Rover Craftsman so maybe that one was 1981 to 1982.