I used to have one of those rc blimps, it was awesome. The thrust from that little gondola is pretty surprising. Which is why I came up with this, a little expensive but you can lift 7 pounds with their smallest model. Here. break>
Since it dosent come with a gondola, get the little cheapy. Here. break>
I guess you'd be able to lift 5-6 lbs with that after the gondola.
If you get a smaller camera. I don't see why the smaller consumer blimp wouldn't hold it up. they even sell one with a color spy camera, oooohhhhh.