My eight-year-old miniature poodle has recently grown quite overweight (we spoiled her to death), and she currently doesn't fit into her harness. I would like to start taking her on walks again to help her lose weight, but I'm afraid to use just a leash and collar as she tends to pull hard on the leash when she gets excited. I don't want her to choke herself, especially considering that poodles are prone to tracheal collapse. However, she is too big for the medium-sized harness at Petco and too small for the large. Where would be the best place to purchase a good-fitting harness for her?