e3 1231v3is the best choice for this budget, the performance is there, a very basic motherboard is all you need for two ram slots and a pcie 3 slot along with usb3 and sata 3, they can all be had on a b85 motherboard for under 60 dollars for now while they last.
the 8320 to reach anywhere near the performance of a e3 1231v3 will need a 150+ motherboard. Getting the 6600 is an option but not buying a decent 120-130 dollar motherboard to overclock would be a waste of a k series chip getting a locked version really doesn't save you a lot of money yet as the b150 or h170 boards are all around 100 dollars.
and maybe 20 on the chip.
I'm tired and i hope this makes sense, it doesn't feel like much but rambling.