Probably not very helpful, but just to reaffirm what others have said. I currently use what was the flagship Yamaha Reciever with b&w cm series and it does a good job but I wouldn’t dream of attaching it to a pair of 800 series. A capable AVR will work and you might even like it, but you’ll be a long way away from the speakers potential.
My friend has a pair of 803’s (older version) and they sing but he uses a very powerful Krell power amplifier to do so.
They need some serious welly!
It sounds like you have your heart set on the 800’s, and I don’t blame you as they’re gorgeous but if you really want a single box AVR then maybe more sensitive speakers. With that said, any speaker in that league will require something pretty special.