It’s unusual to have pet rats. Most vets do cats and dogs, and anything else is an afterthought. While there are many vets within 5 miles of me (suburbia), we have to travel over 30 miles to get to a good rat vet. Vets for farmers know more animals, but I wouldn’t expect them to know rats very well.
One time when one of ours got an X-ray, the doctor was comparing to a photo in a large book of X-rays for various animals. I expect that’s an expensive book to buy.
I’ll give you two suggestions at opposite ends of the spectrum: