@bladeshark is the Everready expert here on the forum. He should be able to give you a firm date based on the pictures and typeset used in the logo. Edit: ahh...he's more of a Rubberset guy. I did some looking, and that sign probably dates from 1918-1924. Radio blades came out in 1918, and the company logo and the 'shaving man' image puts it in that time frame as well. You could probably narrow it down further by figuring out when that price was common in the UK.