Well I forgot to write up my findings.
I went to the Canadian Tire in the east end (Jean-Talon & Langelier). They have tons of Mobil 1 but no 0W-40. I asked the guy about ordering 0W-40 but he said that they don't really do special orders.
I'm going to next try the big auto parts distributor stores (e.g. Jarry Pieces d'Auto).
I did find a 6-pt 36mm 1/2" drive socket at Canadian Tire for about $11. As I wrote before, Sears only has a 12-pt socket.
I'll write my findings when I have a chance to go to Jarry Pieces d'Auto.
Life is fragile