On one of mine, I ground away about about half of the spur, cross drilled what was left and soldered in a bit of drill rod as an extension. Doesn't look like much, but works great and allows a low scope mount. Can't really see it under the scope, anyway.
I've looked at the hammers with a view to a reshaping project. You could grind away some of the underside of the spur, deepen the V between the spur and and body of the hammer, clamp everything but the spur between between aluminum blocks in a vise, and reforge the spur with a torch and hammer. You would have to finish with a file and refinish afterwards and you still would not have enough clearance to cock it under a low scope without an offset.
One problem is that the hammer has to come up from underneath. The hammer has to stay narrow enough to fit through the slot. I had to unsolder my extension to replace the transfer bar. That precludes forging an offset on the hammer spur.