Hello, newbie here. Recently I obtained the set of GB coins. Predecimal era, all of them are 1966 year. But the set itself can be combined later. What is intereting there is the $ sign in the corner. It is engraved the same way as other inscriptions like "Penny", "Coinage"...

exploring the Internet I discovered that similar set also has the dollar sign in opposite corner:

so it cannot be kinda "place for price" $10.99 or similar.
There is no additional information about manufacturer of this set
I am very curious, what this "$" sign can mean? Appreciate any guesses.