Print the thing up, single piece. Get a small rod for the smaller hole, match it to the depth on your camera, and glue it in place with a bit of ABS paste. Then figure out the threading for your camera and get a small screw that matches it, keeping depth in mind. Also, some foam tape on the top will make it easier to get a stable mount. You may have to trim the print a little depending on the rotary lock of your tripod.