Speaker cables for Focal 1038 Be?

Looking to pair speaker cables for my Focals...
Likely to buy used. Ideas, experience! Budget $500-$800...
Any wire of sufficient gauge (thickness) and moderate capacitance and inductance will work just as fine as any fancy megabuck cable - contrary to what wire maniacs will claim! Monster is an easy recommendation! 
True - fat pure copper wire and you're good - Jacques Mahul would agree; that's what they use in their own systems.
 I switched to Cerious Technology Graphene Extreme from some Morrow cable and am very happy with results. I would avoid silver. Best thing I did for these speakers was recently added Iso Acoustics  Gaia feet. Wow!! Huge improvement. Bigger than a component upgrade, improvement in bass response not subtle.Strongly advised

Buy anything but Monster. Noel Lee is one of the biggest Aholes in the business.  I believe he is out of the Audio business now. He was involved in Bitcoin mining and he lost his money.  
@larseand - speakers of this caliber really deserve some very good cables.

I would only consider cables such as ...
  • Silversmith Fedelium Speaker cables  - a pair of 10ft cables is $1400, which in todays world is not too bad. A lot of people on this forum like them
  • Inakustik speaker cables are even better, but more expensive
Anything else will not be doing these speakers justice

If you are into DIY I can recommend an exceptional alternative, but they are for a more advance DIYer

Let me know - Steve
I had a pair of vintage 10AWG Monster speaker cables. These things sounded fantastic. I wish I kept them. It was their top of the line cable then. Thick black insulation. Very stiff, I had to move the component rack away from the wall a bit. 

I may seek out a used pair