I can't see Commies winning Cold War on same mind as Capitalist nations won that. USSR might survive but never can get world domination nor Communismt can't take over the world.
Well, I dont think so. If the Soviets manage to get most of the world on their side, the USA becomes isolated and may eventually collapse into communism. This is not all that unlikely.
(1.Communists could take over or
2.The Soviets bribe the nations into their camp).
And for all those who think that the USA couldn't become communist: Pollitical trends can change extremely fast.
In OTL, the anti-communist opposition in the USSR did only have 0,1% of the populations support in 1979. In 1991, they had taken over the country.
So you see what I mean. The Soviets could easily won the cold war. In fact the book 'Prediction' by Bruce Bueno De Mesquita offers a quite interesting perspective on the pollitical 'rules' of the cold war, its OTL developement and the possibility of alt developements.
So on the original question: Its difficult to say that, because we dont know which could would side with the Soviets in and after this alternate cold war.
But after a 1954 POD, South Korea is a hot candidate (only if there is no second korean war).
The UK may be another possibility (lets say with a more intense North Ireland conflict, or Thatcher-esque prime minister).
Chile if the fascist Pinochet regime survived.
South Africa, if Apartheid survived.
Just some ideas...