Alan,
This is my solution. Hope it helps.
Gitzo GIG1564
G-1564 Mk2 Studex Monopod - Supports 17.64 lb (8.00 kg). Retails for $116.00.
I also use a Manfrotto Quick Release plate with the monopod. I do not need a ball head. I use the monopod with my 70-200 2.8 IS lens. Since the lens has a tripod collar, I attach the QR Plate to the tripod collar . If I want to change the orientation of the camera to vertical, I loosen the collar and twist the camera to the vertical position, and tighten. I have a 1D MkII with this heavy lens, so the weight rating had to be high.
I have had good results with this set up so far. It is sturdy, steady and mobile. I used this set up to shoot a bike race last weekend. Here is the results.
http://homepage.mac.com/robekert/
Rob
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