Okla. Stat. tit. 22, § 22-707: Defendant's subpoenas

The clerk of the court at which an indictment is to be tried,

must, at all times, upon the application of the defendant, and

without charge, issue as many blank subpoenas, under the seal of the

court and subscribed by him as clerk, for witnesses within the

state, as may be required by the defendant.