Which US and non-US national gliding team owns gliders?

No team-owned gliders in Belgium: everybody is on his own. There used
to be gliders administreded by the Belgian Gliding federation or the
regional subsidiaries, but that was in the seventies!

In France, the French Gliding Federation still has a whole bunch of
modern, regularily replaced gliders (World class, club class, standard
class, 15 and 18 m, open class) that are made available to the
national team. When not used in international competitions, they are
at the national gliding centre at Saint-Auban and can be used by any
qualified glider pilot during a soaring camp there. They are also used
by the would-be instructors during the instructor courses.