This question is our own and we've yet to find a suitable answer, despite doing a fair amount of research into it. Is there a way to sort search results on Amazon to reflect 'Amazon-only' orders? Which is to say, orders that are sold and shipped directly from Amazon?

We are Amazon Prime users, so we always want to be able to claim our free two-day shipping, which only applies to orders from Amazon directly—not third-party vendors.

It could be that Amazon doesn't want to make the method available because it might perturb their sellers, but that hardly seems like our problem. Any ideas?

(While we're at it, we wouldn't mind being able to sort by 'in stock,' as well.)

Update: Reader Aviva notes that "Apparel & Accessories already has a link "Shop Direct from Amazon.com." Bastards! That's what we want, but everywhere.