[strike]According to Antec's site, the ISK 600M is actually mini-itx: http://www.antec.com/product.php?fid=5022033&id=706714&lan=nz[/strike]
Edit: nevermind, that link is for the 600, not 600M. The 600M does support a slim ODD, is that not an option for you?
This one is pretty darn close, but exceeds your dimensions by 0.3":http://www.newegg.com/Product/Product.aspx?Item=N82E16811129228