
For the sake of a month or so I would leave it till after Christmas. It is unlikely that you would find someone breeding to the quality and health that your mother would want with a litter available just now as most responsible breeders avoid this period if at all possible.
Not sure if you mean a King Charles Spaniel which are actually rather rare of the more popular Cavalier King Charles but here are the Breed Club details of both. I would strongly recommend that you source your breeder via the club as their members will be breeding to their code of ethics including the very vital health screening that will help prevent you buying a puppy with the medical problems these two breeds can sometimes suffer from. The breed clubs will be able to advise just what health screening is expected of their members and what the desirable results would be. Ask for prove of results in certificate form.
KING CHARLES SPANIEL ASSOC. Sec. Mrs M Moss Tel No: 01273 493582
KING CHARLES SPANIEL CLUB. Sec. Mrs T Jackson. Tel No: 01934 822758
The cavalier club