Old bottle of Dewar's
Hey there mchomin - our apologies - we must have overlooked your request. My best guess is that your bottle is dated to be from 1926. Earlier Dewar's bottles include a date in the bottom right hand corner of the label - for example '5/22' would mean May 1922. Your bottle has a 6/26 (thanks for including that close up) which would indicate June 1926. If your bottle does indeed have a cork, then that would further confirm at least an earlier date of the year 1927. This is because at some point during 1927, Dewar's starting replacing corks with metal spring caps (which were then replaced by modern screw caps in the late 1950s - early '60s). As for value, you'll need to try mctears.com or bonhams.com
Hope this helps!