Mercedes Benz do a very similar plastic clip, but without all the ribs along the strap, and with a pin that spreads out the fastening when tapped into place. The difference being they are easier to open and re-use. I'm told it is possible to open the original ones, but I didn't manage a single one removing two different wiring looms from the engine bay. Sorry, neither a part number or a picture to help you, but ask at your nearest MB dealer spares counter. They look tidier, still somehow 'right' or at least not a glaring change to an older car.