I think that's accurate, although there's a few I'm familiar with that I don't know where they are or who owns them(Dantanlion and Gremory for instance). 

I also didn't know there was a canon Seere. 

I've also seen what [i]looks[/i] like official development art for a handful of others, but we can ignore them. 

There's also TONS of fan art of gundam frames, so there's a lot to pick from if you want reference art that doesn't belong to a canon suit.