DUX Dining Set

My grandmother is downsizing and she told me that her dining table was a DUX piece that she purchased in 1960.  It has always had a table cover on so the wood is in immaculate condition.  There are 6 matching chairs with the original upholstery.  Also, there are 3 leaves to the table, that unfortunately were not restrained when the table was redone in the 1970s, so they are a slightly different wood tone, but in total the table expands to 11.5 feet.  I'm not sure what the set is worth, so any insight on this would be greatly appreciated!  

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