Hi there, I would recommend checking out specialized automotive tool stores or websites that focus on BMW diagnostic tools and equipment. One reputable online retailer that comes to mind is ECU Tools (
https://ecutools.eu/). They offer a range of cables and tools specifically designed for BMW vehicles, ensuring compatibility and reliability. It's always a good idea to look for products that are endorsed or recommended by enthusiasts and professionals to ensure you're getting high-quality, reliable tools for working with your car's control units.