Browsing online for cheap toys to use in Stargrave, I came across the Space Union line of sci-fi sets, advertised as "Space ships for your space war." According to the packaging, this toy line is made by Peng Rong out of China. I found two items, once looking like a SHIELD helicarrier, and the other like a more conventional science fictional vessel.
These toys have a lot of potential in my scenarios as objective, opponents, opportunities, or even just scatter terrain. Unfortunately, the low price of these sets means the undersides of most of these vehicles are hollow, but that won't be an issue in most games.
Still, it's a lot of bang for your gaming bucks. These spaceships just need some new paint jobs, and they'll be ready for use as terrain features or objectives. Their size means they will block line-of-sight and provide vantage points, which will make tactical situations interesting. All in all, I'm happy with my purchase.
Now I'm off to work on my space ships for my space war.