As has been said before is just how stalinist do you want it? All things are relative, I mean Kruschev was quite the stalinist when compared with harry truman, so the issue becomes just how much of an adherent to Stalin's particular ideology is his successor? Obviously, no one is going to make it a seamless transition where you wouldn't notice the difference between stalin and his successor, changes were guaranteed, but someone could always try their best to run the SU as close to the wishes of the dear departed Stalin as possible(I'm guessing either molotov, or maybe beria?), right down to the planned invasion of eastern europe. Or they could maintain the domestic policies only marginally the same as stalin did with perhaps slightly more rapproachment with the west, honestly anybody who looks at the respective number of nukes and intercontinental bombers on either side of the iron curtain in the early 50's has got to realize that a war will be disastrous.
Of interest is the cause of stalin's death, if he is assassinated in TTL, then whoever takes the reigns afterward may be even more paranoid than stalin was, seeing the last guy to hold your job get bumped off can do that. Although remote, such a situation may result in a renewal of the purges, however I'm guessing only one or two of the key players would be that insane, maybe Beria would(although I think he may have just been ridiculously evil, not crazy).