There are quite a few companies that advertise online that offer high pressure laminate cut to size.....It tends to vary in thickness from about 0.7mm thick to 1.0mm thick, depending on the quality.
Having done a quick Google search for this I can see the problem you're coming up against. Plenty of pre-laminated boards but little in the way of the laminate itself
There are, as said, many companies selling the board and, seemingly, some able to "make up" to requirements?! Maybe, approaching one of those to see if they'd be willing to provide your needs OR, failing that, a name/contact for a supplier of the laminate could be your best approach?