Okla. Stat. tit. 6, § 2023

A credit union chartered under the laws of the State of Oklahoma, the member accounts of which are insured under Title II of the Federal Credit Union Act, may exercise any of the powers of a federally chartered credit union doing business in this state, until otherwise provided by the Legislature; and provided that the State Credit Union Board may by rule prohibit the exercise of any such power if the Board finds that the exercise thereof will not serve the public convenience and advantage and will not equalize and maintain the quality of competition between state and federal credit unions.