Pretty much bog at "Yantar". Also, armpatch: "ДОСЛІ-" without latter half can have a lot of meaning. It would be either suit's name/type ("experiment(al)"), sort of test date (given circumstances, it probably must be checked quite often) or "researcher" (given the photo).
Overall it has a weird pattern unless seen as a whole.
P.S.: There's no generic KSRI, but quite a few specialized ones.
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