Etsy artist Jess Firsoff makes NES cartridge rings. All you have to do is insert them into your loved one’s front-loading cartridge ring slot. You can ask her to make a cartridge stud out of any game, including the famous gold cart of The Legend of Zelda.
If you don’t specify your game of choice when you place your order, Jess will just make you a Mario Bros./Duck Hunt ring.
Jess normally sells the NES cartridge rings on her Etsy store Oh My Geekness for $25 (USD) each, but she temporarily closed the shop “for a few days” so she can work on her exams. I suggest you use the time to decide which cartridge you’d like to turn into a ring.