Okla. Stat. tit. 14A § 2-413
With respect to a consumer credit sale or with respect to a consumer lease the agreement may provide for the payment by the buyer or lessee of reasonable attorney's fees not in excess of fifteen percent (15%) of the unpaid debt after default and referral to an attorney not a salaried employee of the seller, or of the lessor or his assignee; provided, however, that no attorney's fee shall be allowed if the amount financed is One Thousand Dollars ($1,000.00) or less and the credit service charge exceeds ten percent (10%) per year calculated according to the actuarial method. Provided further, however, a court may award reasonable attorney's fees to a prevailing litigant in any transaction where such fees may be awarded in accordance with other statutes of this state. A provision in violation of this section is unenforceable.
Okla. Stat. tit. 14A, § 2-413