Bullion Kings Crown with Royal Blue Cushions.
 

I was given this badge about 30 years ago.
Unfortunately the person who gave it to me had removed it from the right lower sleeve of a shell jacket in order to replace it with sergeants chevrons and wear the jacket as part of a Victorian Grenadier Guards reenactment costume.
As I recall the shell jacket had white metal Grenadier Guards design buttons which I took to be HAC.
There was an extra.button along the front of the jacket (9 of them instead of 8?).
I was puzzled by the cushions of the silver bullion crown being blue instead of red and a few decades on have finally dug the badge out to post images and ask why the blue instead of red please?
Could the jacket be colonial rather than British?

I forgot to mention, the badge is 5cm tall by 5.5 cm wide.

More likely Police.

regards

Strange, from what I remember the jacket looked genuine enough in terms of the buttons etc but there's always the possibility I misidentified the buttons.