I have had this pin in my possession for the last 5 years, and would like to know what its approximate value is. My grandfather served in WW2 England, and I am familiar with identifying the age of this, as this was within his memorabilia from his time there.
It still has the red enamel on the crown area, and the blue enamel on the banner. The fastener is a long bar and straight/safety pin type. The inside/back of the pin, the word silver is stamped into the bar which itself is slender, not wide. It was originally golden in color, but time has tarnished the pin and it shows mostly silver. Overall, it is in good condition for its age.
I have noticed that the "newer" pins boast a green colored banner, and that many others show a more ornate looking crown with large plumes of feathers. Mine, however, doesn't contain such a dramatic styling on the crown, and maintains the blue banner.