You can knock ££££ off that by using a local Indian operator.
Not only will it be cheaper, but it will be so much more enjoyable. The problem with going on a group tour, is that majority rules. That means, if most of the people want to stop at a carpet shop, everyone stops at a carpet shop. If the majority want to go back to the hotel and lie by the pool, rather than travel by rickshaw through the bird sanctuary, then you all go back to the pool. I speak from experience - both those scenarios happened to us on a group tour in India.
With a private car and driver, you have total flexibility. You stop when YOU want to, you plan your own itinerary, you choose your own hotels. India is not the place to go all-inclusive - there are so many wonderful local restaurants to choose from, and eating out is incredibly cheap by English standards.
The last two times we went to India (we have been seven times now - we LOVE India), we used a local company called Icon India Tours to arrange the trip for us and were very impressed indeed. Like you, I had seen a tour from the UK, and Icon did it at least 30% cheaper. I loved having my own driver - someone to recommend restaurants, and take me there. I don't like shopping, so we arrange to avoid the tourist trap shops. On the other hand, I love photography, and on group tours I always get left behind when at sites - whereas on a private tour, we can stop the car when we see something interesting, and I don't miss out on anything at sites.
Here's the link if you're interested:
If you want any more advice on planning a trip to India from the UK, feel free to ask.