Speaker Cables : Moderate priced

Mogami  3103 or 3104 for speaker cables,  and 2549 for interconnects. Excellent quality and performance. 

Mogami is the cable you use when you either sold your good cables and have the mogami as a backup to hold you over, or are listening to the system that’s on the level of mogami…low-fi or lower tier mid-fi. It has no place in a good system as it will limit its potential. 
I personally prefer Canare 4s11 speaker cables and Blue Jeans interconnects to any Mogami including Studio Gold. They sound fuller and more natural to me. 

Highly recommend Mogami as a primary cable.  My experience is they dont' subtract anything, while high-end speakers rely on some subtraction to create more imaging or detail.  Markertek has both single and quad types.

I would have a careful look at DHLabs cables. These are my goto budget cables and interconnects. Many folks will recommend them, top notch, reasonable cost.

Are these your current speaker cables? They have several desirable attributes such as the type of copper used, the gauge, and the dielectric material, i.e., 12AWG Long-Crystal Oxygen-Free Copper and PE dielectric. What do you expect to improve by switching to different speaker cables?  I doubt you would reliably hear a difference (much less an improvement) between your current cables and any of the suggestions here. I suspect there are other areas of your system where the $1,500 could have a greater (at least audible) impact on the sound of your system.

Back in November, you were interested in tinned copper in cotton speaker cables. Were you ever able to try a pair of those?