Sarg

The barrels are chopper lump, the dolls head extension is part of the lump forging, the section on the flats of the barrel or that you take to be part of the shoe is an aesthetic extension of the barrel reinforcing designed to run into the fences on the action and bar and created by filing and striking when the barrels were joined to the action, many english doubles exhibit this feature especially those with the Osborne name. It can certaily give the appearance of a shoe lump construction, but generally guns of this vintage will be chopper lump with the occasional dove tail lump still seen.