Yes. Although the name of this blessing is the “Priestly Blessing” it may be said by anyone. The text of the blessing is found in the Book of Numbers, chapter 6, verses 24-26:
May God bless you and guard you.
May God shine His countenance upon you and be gracious to you.
May God turn His countenance toward you and grant you peace
True, this is the blessing that is given by each Kohen to the congregation during services. Not during services, however, it is also “kosher” and appropriate to say this beautiful blessing. In fact, there is a widespread Jewish custom for parents to bless their children with this “Priestly Blessing” every Friday night (even though the parents are not Kohens). Our Sages teach that the Priestly Blessing contains everything that a person could want.