Hi Tony,

Well, I cannot claim that anything I did was the "proper" or best method...
The curved region was done using the tree rings as "contour" lines, like in a terrestrial map of elevations.
This assumes that the grain was straight and parallel to the center plane of the stock, which may not be true, but
given the taper of the left of the stock, and the way the tree rings taper, it looks fairly parallel.
So the curved portion should be more or less accurate. They may need to be redone, or made less shallow...
In Top view, placed a lot of dot points along a curve. The leftmost dot was placed at high z, starting from the far left loft. The rest of the dots occur at z = 0.
In Top view, starting with the high z dot, doing a freeform arc through all the dots, created a curve with constant high z value. The curve did NOT drop down to the center plane. Then did lofts or sweeps... This was time consuming, and the result less than perfect.
The naked edge test showed a lot of edges, so some fixing may be needed...


The two rounded, right hand red extrusions were quick and easy. In Right view, the right end picture was aligned to match the base of the handgrip, and
the top (back) of the rounded area. Then the thickness was estimated, and one (or two) rectangles made. The rectangle is extruded to be larger than the
front rounded area. Then the centerline top profile of the rounded section was extruded in the plus and minus z directions, beyond the red areas, and used
as a boolean difference to trim the red 3D rectangle solid. (A common and good technique). (Had some trouble with disapearing red portions, so should have just done one red block, and then copy it...)

Made an assumption that the stock is not right handed. (That the bottom half is symetrical with the top half.)