Well, they are as official as any of Mongooses stuff - they were part of published supplements done under license and supervision of WB. Originally they both came from the now gone space combat game "Babylon 5 Wars" by "Agents of Gamings". And were now re-featured in another licensed product.
There are a few nice pictures of the Hermes scattered through some of their supplements, as AoG had a CGI model made for it.
And a miniature of course. this being a mini game mostly (OK, so they had counters too, but those didn't look a tenth as goos as a painted mini, and were annoying to play with anyway - sure, they had the advantage that you could stack them and so have multiple ships in one hex, but they also had the great disadvantage of a gust of wind scattering whole battle fleets...). It was one of the last full-scale minis AoG produced... and looks rather nifty.
No such luck on the Daggarden, only the shiluette from it's Ship Control Sheet gives you a hint on how it might look (a nice asymmetrical design).