This is a 1950's-1960's Hans Wegner style folding chair with rope back and seat. These chairs were made in Italy, Yugoslavia, Germany and Japan in the 1960's inspired by the Danish designer Hans Wegner. Companies like Otto Gerdau and Scirocco sold these chairs in the US during this time.
There was also a designer named Ebert Wels that designed a similar chair in 1928. Yours is not a Wels or a true Wegner because on his chair the back was 'flush'/even across the top. You have the vertical sides rising above the horizontal slat by about 2", which is not a known detail of the Danish chairs.
The value of this chair is $200 to $300 retail and would be $600 if it were a signed/labeled Hans Wegner.
Some sites that I recommend are Varagesale.com, Chairish.com, Ioffer.com, Furnishly.com, Deconet.com, Lushpad, Krrb.com, and letgo.com.
You can also go to invaluable.com or liveauctioneers.com and search their directory for an auction house near you and consign to them.
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