This USB cable from LavriCables offers high-end build features (including separate runs for data and power and 5N silver conductors) for much less than you’ll find elsewhere. They don’t list USB-C as a standard connector, but I know they’re open to building custom cables so wouldn’t surprise me if they might be able to accommodate you for your specific needs so worth an email I’d think.
https://www.lavricables.com/cables/ultimate-silver-dual-usb-a-b-interconnect-cable/
Another option would be the DHLabs Mirage that looks like it offers USB-C as an option…
https://www.thecableco.com/cables/usb-cable/mirage-usb-cable.html
Best of luck.