Unofficial WW2 Warden's LARP Instructor Embroidered Badge

It is assumed that the badge below was a private purchase badge that was worn by member's of the Wardens' Service who had passed the LARP (Local Air Raid Precautions) instructors' course. The silver coloured enamel badge is regularly available but to date the below badge has not been seen on any period photographs. I have seen several of these badges over the years and they all appear to have the same style of manufacture.

Unofficial WW2 Warden's LARP Instructor Embroidered Badge