Yorkshire Terrier Puppy Wanted

I am looking to buy a littly Yorkshire Terrier for my mother who lives in Germany. She always wanted one and it would be a surprise of her life time. Ideally I wanted to surprise her for Christmas but I am struggling to find a respectable place that would sell those lovely dogs at an affordable price. I am willing to buy the dog in the UK if it has all the travel documents to fly with me to Germany. I never had a dog myself and I am not sure how difficult it is to transport a dog from one country to another. Would very much appreciate any advise you can offer. Many thanks in advance! Inna