If you are trying to stay under $500 -
For the past few years, I have been using ANTICABLES Level-3 Power Chords and am quite pleased with them. They sound better than stock chords and start at a sensible $330 (more $ for longer lengths). I have never used their Level 2 Power Chords.
I have no affiliation. If you want, here is the link: Level 3 Power Cord (anticables.com)