The links you mention are puppy mills that produce some very poor quality and sickly pups. If you do an internet search for Yorkies for the most part you will get fancy ads for what are basically puppy mills. They breed dogs without any concept of proper breeding methods and keep their dogs under horrible conditions. Just here on YT there are many people who show up with sickly and even dying puppies and puppies that they are not even sure are really purebred. There are also a large amount of what we call backyard breeders out there. They do breeding on a somewhat smaller scale but also have horrible breeding practices.
Have you looked into how you would get a puppy out of the US and back to your country? There are usually laws concerning the transport of pets between states and countries that require certain shots and health certificates. A puppy may not be able to meet those requirements depending on your country's and the airline requirements.
There are reputable breeders in Texas but to find them you need to make the right contacts. You might try going to the breeder section to post a request for info on good Texas breeders. I would recommend that you look for a well established breeder that has a record of producing sound puppies. I am posting a link to the AKC website club search area. If you look for clubs in the state of Texas and then click on details you will find the contacts list for the club will show the breeder referral person. Try contacting them for a Yorkshire Terrier breeder that they would recommend
American Kennel Club - Club Search and Directory
We have a terrible problem here with irresponsible people breeding purebred dogs without any regard to proper breeding practices or genetic selection. There are many scams being perpetrated on people who do not know or understand proper breeding of purebreds. You will find puppies every where but the health and quality is very questionable. The Yokshire Terriers that are the result of these breeding practices now carry genes that produce severe genetic defects such as liver shunt and luxating patella. Pet stores almost exclusively sell puppy mill stock.
I hope you enjoy your visit.