Jack I can get you some pictures of cans that I doubt you have ever seen I've got a Pace can from around 1957, a Scott-Bonnar/Flymo, a 1930's lawn mower oil can, and the list goes on!
Also regarding a date on this can, Castrol starting using this logo around 1958, so we can narrow it down to 3 years.
I have also seen many others on Facebook in other peoples collections that will blow your mind!
I've got a Pace can from around 1957, a Scott-Bonnar/Flymo, a 1930's lawn mower oil can, and the list goes on! 
