Xtracolor (enamel) and Xtracrylic (acrylic) are produced in gloss, covering the ranges of WW1, WW2, 'Modern' and airliner colours, and have been around for over 30 years.
Those colours for internal use that are matt in real life, are produced in matt in both ranges, and shown as such in the paint listings.
I'm slowly changing back to the Xtracolor, as even the so-called 'new' Humbrol is still poor quality, compared to the original paints.
Far as I know, the North American agents are Squadron, and handled in the UK and Europe by Hannants.