Arteriovenous malformations (AVMs)

Dear fellows,
My son was discovered a Arteriovenous malformations (AVMs) in the pelvis, It was treated in Mayo Clinic almost ten years ago, however the mass was not removed for being so close to the main artery. He noticed the tumor is affecting his leg mobility and causing a lots a pain. The Radiology recommended to do a follow up every five year, unfortunately he is no longer has health Insurance, he pays Obama Insurance but his plans doesn't cover any medical service if not in the plan. I would really appreciate your advise how to get a MRI at Mayo Clinic a lower cost.
Sincerely,
Elidia Griffin- Mother
Son- John E. Griffin