What ICs to connect pre to power amp?

I want to upgrade my RCA cables connecting my pre-amp to my power amp. The problem is, I'm running 6 channels, so I need 3 pairs of cables, and really good ICs will be too much to spend-- I currently connect my CD player to my pre with Clarity Labs Foxfire. Any suggestions for a solid IC for this purpose that won't break the bank? I have a general thought that I don't want to spend more than $50/pair and I have no problem buying (gently) used.
I'm also curious as to whether you all regard this connection between pre and power amp as one that merits the use of great ICs.

Lastly, would it make sense to buy a nice pair of ICs for the channels connected to my main speakers, and lesser cables for the rears and center speakers, or would I create an imbalance between the channels?

Thanks for input.

D