This is a beautiful ring that I designed for a client. It features a Celtic knot on the ring and a heart shape in the center. It also has two slots for gemstones. This ring can be modified for your use and you can then buy a physical copy on shapeways dot com.
You can use this however you please as long as you do not resell it or use it without giving credit where it is due. Designers: Robert Boyer, Ben Jewkes.