Front Sight Identification

[brickie501]

Bit of a long shot this one...

Can anyone identify the front sight blade on left below?

It came unidentified as part of an eBay job lot of SMLE & Enfield No4 rifle parts but it doesn't seem to be for either of those



I've pictured it next to a standard No4 front sight (right) for scale & you'll see it has a larger 'blade', but the dovetail is also noticeably larger too.

It looks familiar to me somehow but there are no visible markings & I've drawn a blank in trying to ID it so far! Any assistance gratefully received...

[Narcis]

Probably for a pistol or a revolver ...