On the hunt for best phono cable under $1k

If by phono cable, you mean interconnects....

I've been satisfied with Herron Audio cable. It's not that expensive but performs very well with his equipment. Haven't heard it with other equipment.

My experience is that if you're looking for warmth, remove all the cable from your system that uses silver and go with all-copper cable. My opinion is that silver adds an artificial treble peak and dries out the sound. YMMV.

As @Stevecham states without the need for ground wire any RCA should work but before you commit to an unshielded RCA IC, make sure you don't have a hum issue. From turntable to phono stage is where this issue may present itself and may necessitate a shielded cable.

SignalCable (special order Silver cable+silver connectors+Furutech DIN)

Here is one idea that is much cheaper than the other options discussed but MUCH more difficult to implement.

Hard wired low RCL cable: 1 uninterrupted run of cardas litz straight from the cartridge into your SUT with shield attached only as it comes out of the base of the tonearm board, than another very short run of low RCL shielded and hardwired into the phono in. Many options are available, cardas is one. No need for expensive connectors, when your hardwired, of course you give up some flexibility in this configuration. I dont know that you can get warmth out of a cable, but your equipment can accomplish this when connected with cabling that is transparent. Just my 2 cents. Best of luck!

Get in touch with Drew Baird at Moon-Audio.
He will make you a custom cable with the minimum length you need for a reasonable price.