Speaker cable recommendations with Magnepan .7s

I’ve done several upgrades to my setup. I’m now trying to catch up my cables. I’m interested in finding speaker cables that will be well suited to my system. I would like to spend under $200 and prefer to buy used.

I have read that anti-cables or mapleshades are often recommended. That’s all I know.

Magnepan .7
Rythmik F12 Sub
Don Sachs SP12 tube preamp
Van Alstine Fet Valve 600r hybrid amp
IFI Micro iDSD Black Label USB DAC
Bluesound Node 1 streamer
Blue Jeans Cable interconnects

Magnepan's do not need any particular cable as they present a fairly simple load to the amp, i.e. not a complex impedance.

They do need an amp capable of good current delivery into 4 ohms.
Clear Day Double Shotgun. An 8' pair sell for $450 new, I got mine used for $250. Great with Maggies and Eminent Technologys.
+1 bdp24 for the Clear Day Double Shotguns. These are meant for low sensitive loudspeakers. Try to find a used pair.
I owned the .7's and loved them, just couldn't do them justice in my small place. Anyway, I used the Anti-Cables and found them just fine. I have also used Blue Jean Cables with pleasing results. Personally, I feel that there is a lot of, let's say, hyperbole out there about cables. I never felt compelled to go into the lunatic fringe with them. Anti-Cables are very simple, very stiff which some people like but I don't. However, many Maggie owners use them and are very happy. Oh, and the price is real world....
I used both Anticables and Clearday Double shotgun before with MMG. Both sound above their price points, especially if you can find them used.
Although this will sound absurb to all readers the price is right and the sound is good. If you havent tried this then don't knock it.
10 or 12 gauge solid copper wire that you can pick up at Lowes or HomeDepot etc.

lak opened the door so I'll chime in with my experience. I recently bought a pair of MMGs which is in a room adjacent to the rest of my system which consists of two separate (and different) amps being fed by a single preamp. The "other" amp is running a pair of MLs in that room. The MMGs are connected to my amp via a pair of 20' solid copper 12 awg wire - certified for in-wall use, run through my basement and bought from Home Depot. Before doing this, I hooked them up to the amp using the wires I use for the MLs which are older but good quality 8' MIT cables. Aside from differences due to the room, I honestly can't say if the long wires hurt the sound. I think they sound great as long as a low gauge/thick cable is used. This is of course not a scientific A/B comparison so YMMV, for sure.

use zip cord, then 'rent' anything cheap and do a blind test

then 'rent' a more expensive cable & repeat the blind test

Better use of your time & money: a nice Bryston amp
I had a Bryston 4B-ST for about a year. I just upgraded to the Van Alstine. Other than the Bryston's sharpness, which I liked, the Van Alstine is a superior amp.  A completely different class 
Maggie uses Bryston amps to demo their speakers at shows.  Give them a call so they'll have a heads up.
Good question.  Or despite refusing to recommend equipment to go with their speakers, maybe they might let slip a cable rec.
Magnepan introduced the .7 with a Conrad Johnson amp. 2275. But I can't make out what the cables were 
With low impedance, you need fat cable like the belden 5t00up.  Exotic cable with $200?  Kimber 8VS.... fat with lower inductance.
Never been able to get a speaker manufacturer to recommend a specific cable. Good luck...