I'm not seeing anything obvious for a marriage in Canada - but then marriage records are not public here in most provinces, & particularly for that time frame. Ontario has made marriage records public up to 1927 & British Columbia through 1932. In other provinces, we rely on newspaper announcements & such as there are no indexed records available.
(I doubt they would have had an announcement if they were on their way travelling through.)
If their trip is as you surmise: England-Canada-Australia, then it is likely they came in through Port of Quebec (or St.John New Brunswick if the arrived before the ice break up in the St. Lawrence Seaway - Dec-late Mar), took the train across Canada & exited for Australia through the Port of Vancouver.
If you think they married on board ship, either from England to Canada or on the way from Canada to Australia, you may want to contact a Chatter called Seaweed. He seems to be the most knowledgeable when it comes to finding maritime records.
If you have the arrival date in Australia for the Aorangi, that may help to track down travel records for the couple & you may be able to determine their status on that leg of the trip.
