In most typical listening situations, I would think that the VAC would work reasonably well with the Harbeth 30.1s. I hear 30.2s a lot with small tube amps and the combination sounds pretty good. For less money, I recommend the ProAc D2 (stand mounted speaker) or the Response 2 (tall, floorstanding speaker); I actually prefer these to the Harbeths, though both brands are good. If you can place speakers reasonably close to the walls, a used pair of Audio Note AN-E, will be in your price range and that is quite a nice sounding speaker.
Near $3,000, you can get Tekton Double Impacts. I only heard them at a show, but, they sounded very good for the money. In the same price range, I also liked the Rethm Bhaava, another speaker I've only heard at a show. These are both quite efficient, so they should really work well with your amp. The Zu Omen is another possibility--they are very dynamic and exciting, but, for my own taste, a bit too brittle sounding (but, I've mostly heard them with solid state and tubes might do the trick with this speaker).
Near $3,000, you can get Tekton Double Impacts. I only heard them at a show, but, they sounded very good for the money. In the same price range, I also liked the Rethm Bhaava, another speaker I've only heard at a show. These are both quite efficient, so they should really work well with your amp. The Zu Omen is another possibility--they are very dynamic and exciting, but, for my own taste, a bit too brittle sounding (but, I've mostly heard them with solid state and tubes might do the trick with this speaker).