Like to hear your ideas.
I made a set using two 3/4" 48" dowels held together by a garden hose O-ring. Tried a regular O-ring, but it just rolled down when setting the rifle on it. The square edges on the garden hose O-ring keeps it from sliding down, but is still adjustable.
My oldest boy (9) just shot his first rabbit this weekend using it and a .17HMR.