Well, at least the Mercs were only carrying Gauss weapons, but judging by the size of the ship there certainly were plenty, plus probably the usual two tanks that could just blast your pachyderm...
I am curious what you will say to Siberia...
Yeah, I'm sure there were a lot of them. From memory, I think that kind of ship is a frigate.
As for Siberia; do you mean the special enclave mission, where you get the Russian files? I don't expect to discover the location of that for a long time yet. I'm still in the first year of the game. At the time of that screenshot, my soldiers were using things like camo paint and hammers...
However, I recently managed to tail a government military transport (I don't have hyper-wave decoders, but I recognise the style of ship). Capturing that ship was highly lucrative! It's still very early in the game, and now I have a few suits of combat armour, and two defender armour (1 damaged). I also got a rocket launcher, a mortar, and a few other big guns. So next time I meet the mercs, they won't know what hit them! (They'll probably be like
"hmm. I wonder what that thing we just squashed was", but at least they'll have noticed us!)