At purchase it wasn't obvious how to select the optional HDMI 2.0b connector. I figured this should be something one could buy later if required.  I've tried looking and I cannot find where to buy the optional third port.

I am fairly sure I need the HDMI 2.0b adapter to utilize 4K@60 and HDR.
As I understand it, the two DP++ ports are 1.2 and not capable of outputting HDR which would require DP 1.4.

Your assistance is greatly appreciated.

It looks like I need a part number for the HDMI 2.0 connector that fits into #4 on the layout below.