Thanks Richard, I also tried a google search but didn't hit on anything definite, I thought the engraving looked like a ball so I was thinking it was maybe going to be a baseball club, I came across this page for sunlife logo's
http://www.sunlife.com/Global/About+us/ ... cale=en_CA none of which look like the engraving on the case back. I agree it could quite easily be a 'S' or a '5' but leaned slightly towards it being a '5' as it looks to have more of a straight line.....