He should have bought a CSL
I believe the two most valuable works of art ever purchased by the National Gallery of Canada are these two.
http://www.gallery.ca/en/see/collections/artwork.php?mkey=35828
https://www.gallery.ca/en/see/collections/artwork.php?mkey=41892
As I recall the first one was purchased for $1.8 Million in 1989 dollars. At the time there had never been a Canadian work of art purchased for over a Million, despite some pretty impressive and unique pieces of art produced by the Group Of Seven