Bark tree chippings (Ealing W5)

Hi - hope you can help. I have an overgrown garden which needs some clearing and then I will need to put a membrane and bark chippings down. I understand that many tree surgeons have bark chippings and can deliver them locally. Does anyone have any or know someone who does? I prefer to be ecological. it's a beautiful garden with great potential. Hope someone can help. Many thanks, Nina