I've got number 665, engraving looks exactly like that, on a slight slant. Mine is also ex Devon and Cornwall. They insist that their Enforcers were destroyed, so either they were sold off on the sly, or someone bought up a bunch of destroyed Enforcers from them or someone else and put a whole bunch of them together. Mine came with a Pecar scope numbered to an early D&C rifle.
On the auction rifle, the BritishBubba also did a numner on lengthening the buttstock.