What's expensive? I get the basic idea of what you are asking but just going by price is no always the best way to go. Espically with cables and power products. The only thing better than a good sounding, expensive power cord is a cheap one that sounds just as good. I looked at your system and something tells me you may get this already. My advice would be to go with sound quality first and worry about the price later.
Some power cables that have worked well for me with amps over the years are ESP Essence, Richard Grey and Shunyata Alpha (various models). That said, I have yet to find a power cable that sounds better than stock cords for my Ayre V5's.
If you are looking to buy cables and haven't tried The Cable Companies demo program, you're really doing yourself a disservice. I can't tell you how valuable that resource has been for me. I wouldn't do cables any other way.