These are Pet Tag Dog Tag ID Collar Tags Custom Hand Stamped, but I think they would make great necklaces. Would love to have one with my dogs name. Many to choose from on Etsy.
Dog Tag - Pet Tag - Dog ID Tag - Pet Accessories - Custom - Hand Stamped - Personalized on Etsy, $12.95
Dog Tag - Pet Tag - Pet ID Tag Pet Accessories - Custom Hand Stamped Metal Flower on Etsy, $12.95
Dog ID Tags Pet Tag Collar Tag - Pet Accessories - Dog Bone with Crystal Jewel. $12.95, via Etsy.
Soft Grip ScruffTag Dog Collars - Waterproof - Stink Proof - No Jingling Tags - ID Tag always on the back of your dog's neck for easy identification! $29