Tam 3,
But S&W had no wide spur hammers pre war, in fact not until the early '50s. And they never had the two hashmarks in front of the spur checkering which are indicative of the King and Micro design.

Goony,
In reviewing pace40's photos I now see that his hammer closeup does show the King Patent stamping. And in reviewing your hammer spur photo I noticed it doesn't have the 'teardrop' shape on the spur tip like the King and Micro. But neither do the hammers on pace40's K22 Outdorsman and 38 M&P Super King Target conversions, and it seems highly unlikely that they would have some other smith's custom made wide spur hammers. They don't appear to be stamped King either.

As bettis1 has documented, there was quite a 'brewhaha' over Micro's copy of the King hammer.
So we may be looking at different vintages of King's hammer modification and after the court case King may have no longer stamped them as patented since the patent protection was nill; all my speculation of course. But I think you have a King hammer based on the above observations.

__________________
Jim
S&WCA #819