For your BMW 520d, a German-made lower arm bush kit is an excellent choice for quality and durability. You can look for brands like Lemforder, Meyle, or Febi Bilstein, which are well-known for producing high-quality suspension components. These brands often offer OEM (Original Equipment Manufacturer) quality parts that are specifically designed to fit your vehicle. You might want to check with local auto parts suppliers or online retailers specializing in European car parts.