Dave I saw your question so I thought I would post some info :
A Steadicam JR can only handle up to 3 to 4 pds. It is really made
for the comsumer VideoCams. If you are interested in a proline
steadicam I believe there is a nice mide range on for several
thousand . Sorry, but there ain't much in between, kinda silly isn't
it from $400 to thousands. You could always look into the real thing
but for that you will need a second mortgage. 🙂