Make them yourself and get any length you want. 2-pin DIN connectors are available in just about any electronics store (and even Biltema), and 2x0.75 mm2 lamp cord is plenty good for speaker use (heavier than B&O factory cables!).
If you'd rather have molded connectors, I believe the cables are still available at the dealer, and the prices aren't that big.
Although I'd just get the 5m cables and wrap the excess up, you'll want to move the equipment sooner or later anyway...