You are quite lucky to have received a set of these. The ebay prices are absolutely ridiculous for the pair. I've contacted Lego regarding these two mini figures, and they pretty much told me that there are no plans to ever make them available anywhere else. What was given out at Toy Fair is it. And that both Iron Man and Captain America are in the retail sets

As if they're the same thing!
Very shortsighted if you ask me. Limited mini figures? Fine. Hard-to-find minis? Fine. But these two are so awesome, how could Lego not think that the demand would be there for them? The Iron Man is perfect, as his head piece has the helmet painted on. The Cap is cool, as it's the Bucky version of the character.
It's probably the single worst decision since Playmate's Star Trek Tapestry Picard. And that's saying something.