I am aware the Catholic Church still have priests that do exorcisms. Try your local Archbishop first. He should have his finger on the pulse. I dont know if you have to belong to the Catholic Church or not, though. Just ask. If there is a hiccup there, then go to a Spirtualist Church and you will find the right person to do the cleansing. Best of luck.
If you are serious about this, you can get help from Protestants or Catholics. Protestants have Deliverance ministries and Catholics have Exorcists who are appointed by their Bishop.
Furthermore, you must begin to pray daily and lead a moral life---that is not to say you are not already doing so. In short, there is help out there, but it isn't always easy to find. True exorcists are rare. Furthermore, most exorcisms are not a one session deal. Some take many sessions which could last weeks or months.
Whatever you do, REFRAIN from attending a spiritualist church. Doing so will make your problems worse! A medium cannot help you!
Good luck to you. My prayer is for you to locate the right people to help you and your wife.
The Catholic Church will not perform an exorcism unless extensive psychiatric testing has been done by medical professionals whose diagnosis concludes that no medical problem is present. I have written about this. Possession by evil is a reality.