I bought mine 2 years ago from Autozone for roughly $120. It was a perfect fit for our base Sky. It was a name brand hitch.
Like you, we want to attach a storage container. In our case, we'd like to carry our golf clubs which are not very heavy. The one container I narrowed it down to is the large Rubbermaid Action Packer that I hope to bolt to a hitch extender with step. Unfortunately, all extenders with steps I find are for a 2" receiver, not a 1.25", so an adaptor will be required. I don't want to use a open metal cargo carrier because of the extra weight involved. The lighter, the better, especially when cantilevered so far out as would be required with a Sky.