St Roch still exists. It is a street that runs east to west and is bordered by Durocher on the east and L'Acadie blvd on the west. I'm not sure if it's the same ST ROCH that existed at the turn of the century. I can photocopy the map I have and send you a copy if you want.
As for the two entries dating from the late 19th C, I don't have the Lovell directories for those years while this can be checkedout in approximately 2 weeks when I have a chance to visit a Montreal library. Let me know if you're interested.
I should mention that ST ROCH Street in Montreal is located in what we now call PARK EXTENSION. It is bordered by Outremont and the Town of Mount Royal.