Try a Volkswagen dealer, they should be almost universal. You can buy them at Walmart or most any auto supply store here in the states. I'm sure I saw them at Autoroute service plazas in Europe.
2003 Winnebago Adventurer 38G F53/ V10 605 watts of Solar
1999 Winnebago Brave 35C F53V10 Handicap Equipped
1999 Jeep Cherokee, 1991 Jeep Wrangler Renegade and 2018 Chevrolet Equinox Diesel