1945 is correct Lucy, the 17 July to be precise.
Lucy, if you were in my place, would you go with the George SMITH / Sarah Ann LAWRENCE option, it certainly would be the easiest choice? The other choice is to pursue the James SMITH / Phoebe (maiden name unknown) as per Phoebe SMITH'S (Hastings) death certificate?
Sorry, I didn't get back to replying to above, earlier.
Yes ... I would have suggested not pursuing Phoebe (d/o George and Sarah Ann), further.
Or ... suggesting that if you have a subscription to the Ancestry website, then getting in contact with the owner of the
Doherty-Dougherty Jan 2013, tree - who may have further information which might enable you to eliminate this 1871 Phoebe SMITH.
Maybe if you have another "spare" $20 or so

, purchasing the VIC birth record of the last-born child of Phoebe and Horace HASTINGS might be a worthwhile exercise ? That way you could obtain further verification of Phoebe SMITH's birthplace plus have confirmation of all of the children born to the couple. [ VIC BDM records contain a wealth of information - they truly are the "best". ]
It really is a pity that there is no "obvious" marriage record for these people.
I guess you already know that the images of historic BDM records for Victoria are available for purchase and immediate download from the VIC BDM website ?
I'll get back a little later with some further explanations regarding your search.
~ Lu