Bulk cable for rear speakers

Canare 4S11 about $1.60 per foot, used in recording studios. 

Agree with stereo5 about the recommendation for Canare cable. Depending on your gear the 4s8 cable might also work, both are available in either black or gray. A good source for either is markertek.com.

The Canare quad is very good value for the price. That said, if you are looking for more premium options, DH Labs sells some great cables in bulk by the foot. I used 24’ runs of the T-14 for my home theater, which sounded great until I took the theater apart. I did use the Canare many, many years ago and it’s a great value cable in comparison. 

I’m full disclosure I am a DH Labs dealer. 

so how much is the DH labs Cable? My system includes Macintosh monos and b&w floorstanding rear speakers.

These are rear speakers and maybe not necessitating the same High level of cable I have elsewhere

You might look at Furez In-Wall Rated Speaker Cable.  They make a 14awg x 4 wire cable (2 x 14awg = 11awg) or a 14awg x 2 wire cable.  The wire is 99.997% OFHC C10100 Copper Construction (High Conductivity Oxygen Free Copper), in a 7 Bundle Advanced Rope Lay Design.  The other unusual value with this cable is the foamed polyethylene insulation (FPE), which I have never seen at these prices.

I believe these come in either 25-foot lengths or a 500-foot spool.  However, at AV Outlet, it appears that multiples of the 25-foot length ship as one continuous cable, which is what you need.  Price-wise it would be hard to beat a star-quad, 11 awg OFHC copper cable at $0.75 or less per foot.