As noted in my post, "Unless there is a 'lis pendens' filed on the property or some court order preventing the sale", he can sell it to you for whatever he wants. However, if he owes a mortgage on it, he will have to pay that off first.
Without a review of the FULL facts, no one can answer with 100% accuracy.
Again, there are lots of other issues that could be involved. For example, a court could decide that the 'ex'-wife should be awarded 'equitable distribution' of any equity increase during the time of their marriage.
OKLAHOMA PROPERTY DISTRIBUTION: Oklahoma is an "equitable distribution" state. Each spouse is entitled to keep:
(1) the property owned by him or her before the marriage; and
(2) any gifts or inheritances acquired during the marriage.
All property held or acquired jointly during the marriage will be divided between the spouses in a just and reasonable manner. A portion of the jointly-held property may be set aside to one spouse for the support of any children who may live with that spouse. The only factors for consideration set out in the statute are: (1) the way in which the property in question was held; and (2) the time and manner of the acquisition of the property. Marital fault is not a factor. [Oklahoma Statutes Annotated; Title 43, Section 121]