I have traced the D-9 marking on the base back to the Old Quaker Whiskey and Schenley Whiskey brands. Likely in the 1950s-60s era. With some searching you might turn up a picture with a label to confirm the ID.
There is not much of a market for plain 20th century decanters. They need a good looking label, packaging and best yet, the original contents, to have some value.
One does find a lot of plain clear decanters on ebay, for example. Some sell in the $5-10 range but many go unsold.
