Most reputable dealers will do you a deal if you spend enough and an AV9/P7 is certainly enough! Why not go back to your dealer that you bought your DiVa gear from?
Personally, I've been very impressed with Home Media in Maidstone who (as well as being particularly attentive and helpful) happen to have a sale on this month (and no I am not on a commission!). Good luck
The best deal on a bit of kit like that is to look for a good dealer who is near to you and can give you the support you need. It is not a mail order product, and rightly so (for one thing it weighs a ton!). With us (for customers in Kent) we would I'm sure consider negotiating a price, but also if local would help you install it free of charge so that we know it is installed and running correctly. This is a better deal than saving an extra bit of money, taking a day off to wait for the delivery, taking another one when the first date doesn't materialise, and then looking at the thing wondering how on earth to get it up and running *at it's full potential*.
I think you'd be a surprised. Independant hifi stores I have come into contact would also offer this service with an fmj system, or at least install for a small charge (which you could probably negotiate into the cost!). Personally for a system of this calibre I always think it's worth having a rapport with a local dealer for when it's time to talk cables or upgrades etc. I know I always tend to remember our clients systems and their tastes even after a couple years