I have had some success with taking a 1 inch thick piece of squarely cut hardwood and drilling into it well sized and placed holes for the edges of the gouge to slot into, then removing enough material between the holes to fit the gouge in there. Essentially, make a wooden donut with grooves on the inside 180 degrees apart, sized to hopefully slide on with absolutely no play. A set screw can clamp the gouge down. A drill press is needed to keep the holes perpendicular to the front face of the block--the only outer surface that even needs to be flat and true. For a gouge nearly 2 inches, maybe radially split wood would work, as it doesn't warp much when wet. If not that, then endgrain wood, which should not move at all. The fit of the grooves is important; the gouge should not be able to wobble left and right when tightened down with the screw. If the gouge is tapered much in thickness, this could be difficult.