Just look for any that support DTS-X and Dolby Atmos. You'll be future proofed for awhile. Even though the additional 3D aural channels they provide IMO are useless. It is the future codec and is very clever. I support it's object based, simplified channel handling, non aural capabilities. This year there are many receivers even in the $350 price range (after sale prices) are firmware upgradable. Just google search atmos, dts-x, avsforum for a 2015 list.
I don't think you're going to get a receiver with Atmos and DTS-X for $350, at least new.
This Onkyo is close, but not sure which model year it is as I don't follow Onkyo and it doesn't appear to have DTS-X at first glance. Also, IIRC, I think you need additional speakers for Atmos to be effective, right? Not sure about DTS-X though.
OP, look for something with HDMI 2.0 and HDCP 2.2 for future proofing. Check these models out and maybe see what avsforums says about them:
Yamaha RX-V379BL
Yamaha RX-V479BL (a little over your budget, but not much)
There is a summary feature matrix on the page for the V479BL which can tell you some of the ways it differs from the V379, so you'll be able to judge if it is worth the upgrade or not.
The Onkyo I linked above is just a little over your budget too, but personally, I'd stick with Yamaha or Marantz.
I wouldn't buy off of Accessories4less if I was you. For the most part the whole "deal" there is getting last year's models (often refurbished) for cheap.
The problem is, you can't use last year's models if you care about using that 4K TV properly. That TV has HDCP 2.2 support, which is needed for future 4K Blu Ray support. Last year's receivers don't have HDCP 2.2. You are blowing your foot off for future use if you buy off of accessories4less, as most of them won't work with future 4K Blu Rays. You need a new model.
Here are your options in your price range:
http://www.amazon.com/Denon-AVR-S510BT-Channel-Receiver-Bluetooth/dp/B00YAO43YG
http://www.amazon.com/Onkyo-TX-SR343-5-1-Channel-V-Receiver/dp/B00WSED53A/ref=sr_1_2
http://www.amazon.com/gp/product/B00V5VJ3TM/ref=pd_lpo_sbs_dp_ss_2
Of those I vote the Yamaha, as I have had problems with a new Denon model and that Onkyo doesn't include an auto calibration feature (which is a HUGE deal). But any of them will work.
Agree - I'd stick with Yamaha. I recently returned a Denon X3100 due to some pretty major issues with Netflix (apparently there is a known issue with Denon and Dolby Digital+ from Netflix) and handshaking issues with my cable box. I replaced it with a Yamaha RX-A850 and haven't had a single issue. Too bad, because my old Denon 2310CI was a workhorse and pretty awesome.