Sure, I used the following resources:
Radiation Oncology: A Question Based Review (Second Edition)
Amazon product
-Decent book, updated within last year or so, most of the important stuff is in there
Radiation Oncology Study Guide
Amazon product
-Good set of questions to go through to consolidate a section after reading the related chapter in the previously mentioned book
Rad Onc Questions Online Question Bank
https://www.radoncquestions.com/
-Seemingly meticulously updated question bank with realistic questions. There were a lot of repeated concepts, for better or worse, and by the time I had done most of the questions and read the explanations in a given section, the rest of that section got really easy (I guess I learned something? Maybe that's the point?). I used this in the 2 weeks prior to the test once I had read the previous 2 books.
Sprinkle in a little of Hansen/Roach (getting old)...
That's all she wrote. Managed to pass despite starting my job July 1 (highly advise against doing that). Test seemed hard, but according to quartile scores was not close to failing.