Victorian Period Mystery Belt (Grenadiers / Fusiliers/ French 2nd Empire?)

I acquired this Victorian period belt a couple of years ago from a gentleman who undertakes general house clearance, he stated that it was found filthy dirty in the bottom of a wooden box and that he gave it a quick rub over.
The back plate measures 72mm across and 57mm high, the flaming bomb device measures 47mm across and 55mm high, the badge is still firmly secured to the plate with its original crank necked pin (now slightly rusty).
The buff leather belt which would fit a size 38 inch waist bears numerous internal ink stamps and additional made holes.
I have failed to confirm whether this pattern of buckle is British Grenadiers / Fusiliers or French 2nd Empire ? as not seen another, possibly a rarity?.
Please study images in regards to condition.

Code: 50742