Happy to help @strongtogether. As your name implies, we're with you. I'm in medical admin when I'm in paid work. :)
Ask your breast surgeon to refer you to the public system for radiation therapy. They are the overall coordinators of your care. Some people are able to negotiate with the health providers to get an acceptable price. You could check with your wife's breast care nurse, she'd know the ropes locally.
@onemargie might be able to chip in with some wisdom if she's around.
How is your wife doing today @strongtogether? K xox