This a pair of Ikea Benno CD/DVD storage units. They fit in with the Billy bookcase line, as the Bennos are also 79 1/2 inches tall. They are 7 7/8 inches wide and 6 5/8 inches deep.
The pair on the left were screwed together by the prior owner, and I used them as such. The single one on the right has been sold.
I also have enough additional adjustable shelves to make both capable of carrying all CDs.
$40 for both or $25 each.
The price is firm, though I would accept more. :-)