Just popped in to Mateen Greenway's 3d Graphics Pages to see what was new. Can't tell for sure (everything else I've saved has been offloaded onto CD) but these don't look familiar. The American Cavalry Disc look eminently suitable for a model (there are three more views on the site), if you can find the right size of curved tubes, while the British Monitor,
For those of you who don't know about his site, here's a link to his Space 1889 page. Take some time to check out the rest of his site, too. He does some amazing 3d work, from Star Trek to Star Wars to Gerry Anderson.
http://mateengreenway.com/steampunk/Space1889.htm