See if the guy will allow you to find a live tree and cut it /split it up for future bow wood. Black locust, elm, hickory, ash, ironwood would be a few choices other than Osage. They don't need to be large diameter,8-12" will yield enough staves to get started. Just seal the ends and the back if you remove the bark which is a good idea right now. The bark will be easier to remove now that the sap is up.
Unless the tops are Osage, let it go and use your time finding live. Good luck!
Tracy