I have no experience with selecting I2S cables myself. I do have experience though with selecting HDMI cables for my AV system. I can definitely recommend both Nordost, Audioquest and Wireworld.
Recently my Wireworld Silver Sphere HDMI started behaving badly. While waiting for a warranty replacement from Wireworld, I ordered an $10 HDMI from Amazon. Sound quality was noticeably degrading as you might expect from the price difference. Voices from my center channel were less articulate and also the highs were rolled off. It became more difficult to understand what was being said.
I opted to try an Audioquest Forest as my local Best Buy had one in stock. Right out of the box it was an obvious step up from the $10 cable from Amazon. Both articulation and the highs were improved.
The replacement Silver Sphere was another nice step up from the AQ Forest, even right out of the box. It was as if it vanished as I stopped thinking about the sound and just started enjoying what I was watching. This probably had to do with it restoring things to where they had been for quite some time.
So long story short, you might have luck finding a used HDMI at a good price. You won’t need one that’s 4K or 48gbps compatible since you won’t be using it for video. Best Buy listed a few of the older AQ models at a substantial discount.