(I don't know who you're talking about or what the picture is.) I don't think athletes get rings AT worlds. They are sized and then sent off to Jostens/Herf Jones who produces them. The athletes and coaches usually get them a couple months afterwards. So the legitimacy of the ring that person has in that picture is questionable.
You can buy worlds rings online (
here) but the order form suggests you will be verified to make sure you we're a part of/associated with the winning team. It's $250. I assume that the "athletes on the floor" get their ring costs covered by USASF. Anything extra might have to be paid for out of pocket. The gym might buy rings for alternates or injured athletes who were apart of the team but didn't compete at worlds. Or the gym might verify the athlete was apart of the team and leave the cost up to the athlete.
The medal could have been borrowed or a coach might've asked for an extra medal. I couldn't find anything about medals, only rings.