The uniform on the second photo looks like <a/the> Soviet post-war uniform.
I was so uncertain that put no article at all. But I think that is wrong.
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Sign up to join this communityAll three could be correct!
If there are many types of Soviet post-war uniform, and this is one of them, then "a Soviet post-war uniform" is correct.
If you have previously identified a uniform as a Soviet post-war uniform, and you are referring back to it then "the ..." would be correct: "Page three of the book shows US, Chinese and Soviet uniforms ... the photo looks like the Soviet postwar uniform (that you can see on page 3)"
Uniform is sometimes treated as a uncountable noun, with the zero-article.
In this case you probably want "a", based on my deep knowledge of Soviet history.