Okla. Stat. tit. 51, § 51-11: Vacancy within thirty days of election

If a vacancy occurs within thirty (30) days previous to an

election day at which it may be filled, no appointment shall be made

unless it be necessary to carry out said election and the canvass of

the same according to law; in that case an appointment may be made

at any time previous to said election to hold until after said

election or until his successor is elected and qualified.