Exhaust Manifold I.D.-Can anyone help??

Hello Guys,

I am posting this exhaust manifold for a colleague on another forum. It was recently found being used to prop up a skateboard ramp!

The inlet is an exact fit for a Merlin exhaust stub, so we are assuming that this maybe off a Merlin engine. The question is what type of aircraft could it be off? Various marks of Spitfire and Hurricanes have been mooted, as have H.P. Halifaxes and A.W. Whitleys, but nothing seems quite right. The outlet has a prominent fishtail that has a strengthening web in the middle, does this help?

All answers/assumptions would be gratefully received thanks!:)

Kind Regards, Ned.