Just wanted to mention I have an I. Hollis sister to the gun posted above. Mine is in 500 Nitro for Black unlike your 450/400 3-1/4" however.

Weighs a bit more than 11.5lbs. 26" barrels. Regulated for cordite 55gr with a 440gr copper jacketed bullet. (kynoch) Made between 1904-1911. A credible expert on Westley Richards strongly believed this gun was made by WR and retailed by Hollis. The justification beyond aesthetics was the style of the folding leaf sights, the method of insertion of the front bead and the rib texture.

Just wanted to say I appreciated your pictures.