Consider sport horse essentials. I haven’t tried them, but I hear that their products are great and natural
I would recommend like you said, anything made with friendly materials, you can actually find so many things that are made of wood and that can be a great gift, also, plants are a very good gift, and last but not least, you can consider giving money to organizations/ong’s as a present, for example you donate all the money that you where going to spend on that person to schools in places where they can’t afford supplies and then give a card to the person with the action that you did, I find that such a beautiful and original gift....
Stella McCartney's products are comprised of sustainability-source fabrics such as recycled nylon and polyester, organic cotton, and lines of Skin-Free Skin and Fur-Free apparel. I also love R.E.V by Rêve En Vert, which offers too products with organic and natural materials 🙂