Silverwoods Pasteurized Milk Bottle

[Step Back In Time]

I got this Silverwoods pasteurized milk bottle not too long ago. It has no makers mark or date codes. I'm pretty sure the company was located in London Ontario. On the front under where it says Silverwoods, it has an embossed 2 and on the back it says Loaned Return When Empty. Under that it has a 4. I'm guessing that one of the numbers is a mould number, maybe the 4?, but then what is the other number? Maybe a date code? I'm wondering when approximately this bottle was made and how rare/valuable it is. Also anything else that you might know about the company.

Thanks
-Austin