Pikes Peak has some great sinew, I have seen some nice mule deer just off the road...lol
There was a primitive muzzleloading group in that area and they deal with skins and such that you might get some of.
If you can head east into Kansas the side of the interstate is covered with Osage Orange. We come out to elk hunt in September and the Osage balls can be seen hanging in the trees....hurts my feeling not to stop and cut some. May be some members on here that live in that area to trade some staves to you.
Good Luck