Also finding it difficult here in the UK to find and decent thin Hdmi cables that will connect the A6300 and O7Q. I'd prefer not to use adapters on either end.
I consulted on the Xtender HDMI lock. I like that it attaches directly to the Odyssey7Q+ shell and is highly adjustable to accept various cables. It also works great.
One of the biggest issues with HDMI cables is the cheapest way to make the multi strand cable is to just make it thicker. It's actually much harder to make it perform as a thin cable. Thick cables torque on the connections, which make the connectors want to disengage as well as add street that can eventually damage the connectors. The cables are likely to fail first, but the connector in the camera or Odyssey could break, which would really suck.
That's why I like the Hyper-Thin HDMI cables. They are so thin that they don't really push around on the connections, and you can even roll up the excess for decent on-camera cable management. You pay a bit more for them, but it's completely worth it. There are some other brands out there (I think Monoprice has some) but these work great and are available in the various connector combinations you may need.