I have a sucker that I cut last winter in the shed somewhere.  At the small end it shows only abut 1/2" of heartwood thickness though.  It has several  little pin knots where little branches were.  I will take a pic of it tomorrow so I have something to show you.  It might be just what you need, since it don't take much osage to make a bow.  I haven't got to it yet, since I was planning on chasing a ring and those little knots were gonna take more time than I have right now!    I can't remember just offhand how long it is, maybe around 68" and is about 2 1/2" diameter at the fat end and well over an inch at the skinny end.