You could get a local shop or a buddy to weld some 1" wide tabs onto the vertical bars, to move the screw holes out an inch on each side. I can make drawings for you to give them, but they should be 1/8" steel, with minimum 1/4" of steel surrounding around the 3/8" diameter bolt hole. Weld the tab so the tab hole is in line with the existing top row mounting holes. A flat tab will lift the stand 1/8" away from the wall, probably a good thing, but if you want it to touch the wall make angled tabs that weld to the outside of the vertical bars. The concept is similar to the small tabs that hold the tabletop on the stand, but long enough to reach the studs. I think they would extend 1.5" outside the bars. Then you can touch up the little tabs and bolts and the color mismatch would not be as obvious as a larger surface.
Or you could mount 3" wide vertical boards to the stand's vertical bars, then screw the wood extensions to the studs. You'd still need to paint the wood, but with only 2-3" showing it might be less conspicuous than a large board of different color. It needs to be wide enough to have some extra meat to hold up the TT and support the screws so it can't be "just wide enough." But the steel tabs can be very small.
Whatever mount extension you choose, it's the top screws that do most of the work and they need to be screwed in DEEP! Use 3" or 3.5" long 1/4" lag bolts with washers. Make a full depth 3/16" pilot hole in the stud (don't go all the way through!) Relieve the sheetrock around the pilot hole so the bolt threads won't tear up the sheetrock too much.
Another (bad) idea is to veneer the large mounting board that Putz recommended so that it looks pretty. The existing wood cabinet looks good enough, so maybe a similarly pretty wood tone might fly. (not)