The efficiency of those 340's (90dB anechoic, 92dB in-room) certainly suggests that the 1070 could do quite well with them, especially with a sub in the mix to help pick up the really low frequencies. That's just the "on paper" analysis: chas or other owners can offer some first-hand feedback.

Cables can be a source of great debate. The minimum goal needs to be properly-made interconnects and speaker wire of sufficient size for the length of cable being run (which should be a fairly short distance for the mains and center). For interconnects, commonly recommended sources include Outlaw, Blue Jeans Cables, and MonoPrice (although the offerings at MonoPrice are extensive and include some really cheap stuff that I'd recommend avoiding). For speaker cables, I'd first recommend going with something around 14 gauge - terminations can be whatever you prefer (banana plugs are the most convenient but may not work for wall-mounted surrounds and can get a bit loose, while bare wire or spades can be tightened securely with a little more effort).