In the UK they're only kept at Cotswold and this new group at Dudley (which came from Cotswold).
They're not too rare in the rest of Europe though not common, but are generally in large groups where they are kept.
EDIT: The generally reliable Zootierliste.de lists 11 European zoos as keeping the species: Berlin, Planckendael, Brno, Skaerup, Obterre, Jardin des Plantes, St Jean cap Ferrat (nope, me neither!), Apenheul, Kerkrade, Cotswold and Dudley. Not as many as I thought, actually.
EDIT NO 2: Not sure why it's not on Zootierliste but Lodz in Poland has the species as well, kept next to Collared Peccaries for easy comparison!