I managed to order one from ebay, but unfortunately it's not the one. It's 9147C instead of 9146C. It was written for BQ M10 FHD. I guess there is a new one as well. I tried it nevertheless, but it's not the right one. It a bit to wide on one side.
So for now, I'm without a media to test/use ubuntu touch 😞
If someone will find a spare connection cable, let me know. Until then I'll be a passive observer.