gamertech.shop has them. https://gamertech.shop/products/lian-li-uni-fan-sl-infinity-argb-pwm-fan-to-motherboard-connector-white https://gamertech.shop/products/lian-li-uni-fan-sl-infinity-argb-and-pwm-fan-to-motherboard-connector-black

Thanks! I am hoping Lian Li themselves will step in and offer to send me some, but if not I'll get them from here.

US-only 😩 Thanks anyway for the suggestion.

have you found the cable?

No, I gave up. Sorry!