Huvius

I have the exact same gun except mine is covered with engraving and a silver finish. They are great guns.
I have a couple on that Webley Long bar.

Re the 3 1/4", if it comes with it, use it,
if not, don't is the way I look at it.

If you bought a new one, I'd go 3" but
if an old gun in 3 1/4" came up for sale,
I'd still buy it.