I've never heard of that chair being copied but I guess it's possible.
Does the upholstery look old? I've also never seen a Plycraft chair of any sort with anything but black or luggage tan leather or vinyl, but who knows! Maybe they went wild with a few. That color was certainly popular back then.
As for value, this forum isn't for that kind of thing (see "Basic Rules" just below the comment field that pops up when you click on Add a Comment). But these chairs are fairly common so you can look up prices for ended auctions (ebay and whatever else you can find). You won't find many for leather in colors but I'm sure that some people would be willing to pay more for a different look and one that so typical of that era, though you may have to wait longer for those buyers to find it.
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