The TV programme "Boy Soldiers of World War II" shows a Recruiting Sergeant wearing a metal "GR" without crown cap badge.
I've found this short promo for the programme,about 5 seconds into it the badge should be visible but only part of it is........ in the programme as viewed on TV the whole badge is clearly visible.
https://youtu.be/QXEWkx4L9d8
I haven't studied the footage to determine if the "GR" is a "V" or a "VI".
Edit: 10 mins 53 secs into the programme the badge is shown, looks like "GRv".