Hm.. Jones has three sugar free flavours of their colas, and they use only sucralose. Diet Rite's sodas are all with Splenda and Sunett (no aspertame), and I've read that Sobeys carries those (though I've never checked, I should go).
Also the Kirkland Signature diet cola from Costco uses Splenda (sucralose).
EDIT: Wikipedia again lol :
http://en.wikipedia.org/wiki/Diet_soda