We were unable to find a panel/chassis-mounted USB connector. So we made one, and have now made it available to buy. Although originally intended to supply power to projects, it makes all of the USB pins available for use.
There are several for sale on Farnell and Digikey. No doubt other suppliers have them as well. Ebay has plenty too ....
There are indeed connectors available. But none fitted what we needed, so hence we made this one to fit our precise needs.
The market presents product choices, but this one has quite a different design which might - or might not - suit the specific needs of a project.