Ironically, where and when I grew up in Texas, it was considered a weed, and I’m sure most people would have given you permission to cut one. Probably would have paid you if you had cleared out more than one (just kidding; probably not). Things change, and might be different now. Still, nobody is going to shoot you for asking. If it were me, I would carry a big tree pruning saw rather than a chain saw, less mess and would be adequate to cut down stave sized osage orange trees.
I would imagine that most of the cost of osage staves is in splitting the staves, drying them, and selling them, rather than the logs.