Once u cross the boarder, dont talk to any of the mexicans that come up to you. You can but they usually will rip u off. I would just get in a taxi and tell them to bring you to the animal hosipital. (vet) once there you can buy pretty much anything you want. Once u get it then find a mexican on the street to bring it back for you. Make sure you have 2 people one to go in front of him and you stay behind until yall cross the boarder. Then meet and get your stuff. hope this helps