Can you make these two games available through Steam?

Both of these games require DOS emulation to play, and I believe that's not something Steam currently supports. However Bethesda has released both of them for free on their website, so they're still easy to access.

This is not likely to happen as they are already available as free downloads from http://www.eldercrolls.com

Yeah, Steam itself doesn't support any DOS emulation. But, there are several games on Steam that comes pre-configured with DOSBox, like http://store.steampowered.com/app/2280/ and http://store.steampowered.com/app/7760/. Although both these games are now using fairly old versions of DOSBox so it's better to do it yourself anyway.