Occasionally, I go back and look at ends I cut off of staves I got when first started working with osage. I wish I had most of them back to try again.
Take pics of this "sliver"; both ends, the back, the belly and an overall view of the stave and post them here. Concentrate on this stave for now. Make the best bow you can with it and learn more about working osage and bow making in general. From what we can see about this "sliver" you should be able to make a bow of any practical weight and not just a kids bow...unless that is what you want to make.
Leave the other "real" stave on the shelf and out of sight, out of mind for now and concentrate on this one. Patience and concentration are very important in wood bow building. If you are thinking about the "real" stave while working on this "splinter" you will come up with a "kids" bow whether you want it or not. Make the best bow from this stave. After it is completed, no matter what the outcome, you will have a better knowledge of working osage and bow building than you do now. You will be better qualified to make decisions about the other.
I know how you feel not having access to osage or having to buy osage at the retail rate. But once you have made a few osage bows you will meet others that have access to osage and that are willing to share or trade with you. You will be surprised how much is out there and available to you reasonably. It might not be primo staves with no knots, twists or hoop-tee-dos but "bad" osage is still better than most other woods in being able to make something from nothing.
Osage is my favorite bow wood but almost any wood will make a decent(or excellent) bow if design parameters are followed for that wood. I have just completed 2 bows using "second string" bow woods that I will put against any of my osage bows. Both white woods(HHB and guava) but neither should have to stand down to osage as far as performance goes.
You have access to some of the best wood bow builders in this country, probably in the world and most will give you the help and advice you need to become a successful wood bowyer. You, on the other hand have to do it so try not to muddy the waters with thoughts of the other "real" stave. Concentrate on this one, take your time, ask questions, take pics to help us help you and you will come away a better wood bowyer for it. Pat