[Arran]

 The two pieces chipped out near the dial will be the most difficult to repair, you would have to cut a strip out of each to make two patches parallel to the existing grain, which would then no longer mirror the other side of the top, but if it was done neatly and covered with shading lacquer it would not be as noticeable. The other missing piece isn't as big of a deal since it's near the outside corner, it's matching sections are also on the outside corners so they are not adjacent to where the patch would be unlike the ones near the dial hole. In truth I would have to think about the better coarse of action myself, strip off the old veneer and replace it, or repair the existing veneer, you could always farm out the job to someone with more experience or practice on some smaller table cabinets first.
Regards
Arran