Are you planning to tow it behind or store it on the boat?
While I can't find it one their website, you can gat a small Zebec built boat with a rigid aluminum hull that looks to be under 10' long. I know this because the local dealer here in winnipeg has one kicking around. I don't know how much it weighs or what it costs, but here is his contact info;
I believe polaris boats in BC also offer a rigid hulled anluminum tender that is about 10' long, but it is a little heavier than you had mentioned.