A shaver without kashrut certification

My father is not willing to buy me a shaver with kashrut certification because he insists on the leniency of
 Rabbi Moshe Feinstein in his time, and I told him that nowadays this has changed and that there is no one who permits it today, and that I asked on Rabbi Amram’s site, etc., but there is no one to talk to, and he does not believe in this whole concept that emerged in the last generation that shavers need certification. What should I do? This Thursday I am going up to yeshivah gedolah.

Shalom u’vrachah.

You do not have permission to use it just because your father does not want to buy another shaver.

If he is not willing to buy you a kosher shaver, buy one for yourself.