Hi Ida,
Many vet clinics have and use a Doppler which is more of a direct blood pressure measurement and preferred by many veterinarians for ease of use and relatively inexpensive cost. There are some oscillometric or other methods which have a higher cost but have other advantages. Our clinic has the basic Doppler machine (only one model I know of which your veterinarian should be able to price out from their supplier).
I hope this helps.
Dr. Ryan Llera