Vintage help: How to install a 1902 pedestal sink
It appears that your sink is not set up for a cleat/wall bracket but judging on the ring of porcelain on the bottom it is for a pedestal.



I know the boss would prefer not to use legs but if you show her this web page. (Not affiliated). she may find something to her standards.  

I did install a similar sink on wall brackets, the ones you show 
do NOT seem to have a good solid way to attach to structure in the wall. 

You could check with vintage plumbing supplier or habitat restore if, you have one, for a pedestal.