Strange that they put Half A Crown and 2/6. Back then, everyone knew that Half A Crown and 2/6 were the same thing. So effectively it still has the price on it.
For many, many years as I grew up, spark plugs were also 2/6. Ron
Rob, I half wondered whether the 2/6 disappeared as the price had increased during the late 1930s but they probably wouldn't have been allowed to call it the "Half-a-Crown" if it cost more.
The Brown Brothers catalogue for 1939 though still lists it at 2/6d. I'll have to have another go at a time line for these. There are so many variations !
I'm happy with the 2/6 on for a late 1939 Norton but a mid-war BSA probably shouldn't have it. Norton had changed to the Dunlop tin by the latter part of 1940.