Stan: At first I thought it was made as original but on VERY close inspection I think I could detect a forged weld just beyond the first screw hole. There is definitely no brazed scarf joint which I would have expected if the extension was a repair.
The metal of the 'extra' portion is a little different in grain structure and finish from the rest of the top tang but the engraving matches perfectly.
My guess is that it was extended at the 'in the white' stage and then finished off and engraved in one piece.
Is a "forged weld" what you Limeys call what we in the Colonies call a "fusion weld"- ie" no filler added, only parent metal used. Not a TIG, and no brassy color (sorry, old chap- make that "colour", righto?) to show a braze line, sans the black flux "pimple"- assume it is close to our AISI 1018 mild steel in analysis, righto?? Cheers- RWTF- member AWS