"Fits."

Darkstar and Ursa Major are core members of the Soviet Super-Soldiers team, which first appeared in Incredible Hulk #258: that's a Frank Miller cover, with a Crimson Dynamo closer to the 'modern' design giving the Hulk the business. The fourth member, Vanguard, has not received a figure yet; unless you fudge it! 

I had thought Vanguard was still dead, killed off in the not-very-good Quasar-centric crossover book Starblast; which then led to his dad the Presence and sister Darkstar trying to murder Quasar in his last issue. I forgot, the Presence managed to resurrect Vanguard in Avengers #43, the second half of Kurt Busiek's run on the book and some of my favorite comics! I didn't think the resurrection stuck, like Presence brought him back as a zombie or something. Much, much later, in comics I didn't read, Nikolai Kyrlenko would take the mantle of Red Guardian, the eighth, in his sister's title Darkstar and the Winter Guard. Per Avengers #10 (volume 8!) he appears to have retaken the Vanguard name but kept the old Red Guardian costume and shield. And here we are!

There is another Soviet Super-Soldier that received an action figure, if you look sharp: the Gremlin, who was packed in with the Hulk Classics Mecha-Hulk! He was the pilot of the robot, which may have been a callback to Iron Man #229, where the Gremlin piloted a more streamlined version of the Titanium Man armor. (And another, 'modern' Crimson Dynamo on that cover!) Sadly, the Gremlin was killed in battle with Iron Man in his stealth armor--a fairly horrible death, that he has not returned from as of yet.