Did you know there is an International Association of Exorcists? There is and it accepts exorcists of all sorts, as long as they have a certificate saying they are certified. Most religions offer classes in how to perform exorcisms and an exorcist that wasn’t better certification can in fact take a course at the Vatican regardless of whether they are Catholic or not.
In the last decade, the number of certified exorcists accepted by the International Association of Exorcists has grown to nearly 500 members. However, in 2016 the IAE said there were nearly 500,000 exorcists performed. Not all of them by their members and they warn that using uncertified exorcists may result in overcharging (the IAE actually has a standard pricing model for Exorcism services) and that an unlicensed exorcist may make problems worse because they don’t know what they are actually doing it.
Furthermore, you do not have to be a priest, pastor, or reverend to be an exorcist. The IAE has guidelines for who can become an exorcist and if you meet their guidelines, you can apply to take exams to become a certified exorcist. As a side note, the IAE says that they are receiving more applications to become a certified licensed exorcist than ever before and they claim it is a direct result of movies such as The Conjuring, because they have popularized the idea of secular demonologists and exorcist because Ed Warren was both, which almost never happened in the days when Ed Warren became one.
Just in case anyone is looking for a career change that helps mankind. The IAE also has strict rules about how to perform an exorcist and who must be present and how to determine if someone or something is possessed.