Help with Eastern European or Russian signature

Oscar's gallery is closed. Both Oscar and his wife (a very good artist herself) are deceased for decades now, though their daughter, a good sculpter, may still be alive in Florida - St Augustine, I believe.

I'd send pictures to a New York gallery specializing in Russian/East European art.

Search engines are your friend. Any chance you can send a photo or description of whatever is on the back of the painting. If there is a dust cover, remove it see anything on the stretcher or canvas. Replace it or replace with brown paper and double sided tape.

I suspect this is a good'un.

It's been over two weeks since you posted this. Have you tried Google Translate?
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Can you please post a photo of the painting itself? I think I know, but need to see the entire work front and abck-thanks

Well said, my friend. Well said, indeed!