Interconnect

I would recommend DHLabs. I find them to be great value. Then I would try Cardas in your price range.  Thirdly, WireWorld… I definitely have not had much luck with Kimber (meaning, they did not produce positive changes), but it has been a while. 

Belden 8402.  Hands down best value for the money that I've come across.

You have to listen to each in your system.   ....listen to audioquest too

I like DH Labs Pro Studio.

Currently use homebrew solid silver; not much difference if at all.  Pro Studio maybe has a slightly boomier low end.

A PC Triple C Wire Interconnect will be quite impressive at presenting a neutral sonic. The perception during comparisons to other wires used in a Cable, is that the PC Triple C cleans the sonic, in some cases in a comparison, purifies the sonic would be good description.

If one was more adventurous and wanted to exploit this further, using Low Eddy RCA's on both Cable and Amp's will be a experience worth encountering.

Even is a EE is used to exchange the RCA's, the cost for Parts and Labour to carry out a very valuable upgrade on the signal path, can still be quite cheaper than buying into certain cable types.