Mix and match existing receiver+bookshelves+sub with Sonos for 5.1 surround? I've got a receiver with a couple of bookshelf speakers and a sub that I'm already really happy with. I'd like to make it 5.1 using a pair of Play:3 units -- mostly because I have already dipped my toe in the Sonos world and would like to add more, plus it would be really annoying to run speaker wire to where I need the rears positioned.

1. Is this possible?
2. If the answer to #1 is "yes," what components would it take? I'm assuming a Connect plus a Playbar (and of course the pair of Play:3s).