If you are handy with a soldering iron and fancy a little DIY, you will find a converter circuit diagram at the following page:
Usual disclaimers apply if you try this circuit.
kind of expensive but it works great: Midiman CO3 format onvertor. I own one and it does the job. It has TOSlink, coaxial, and AES/EBU inputs and outputs. You can switch between the input formats and ouptut on all 3 at the same time. It also allows you to control the SCMS copy code. http://midiman.com/products/m-audio/co3a.php Might want to keep your eyes open on EBay, that's where I found mine for under $100.
The Monarchy DIP or one of the audio alchemy "digital transmission interface" boxes will probably do what you are asking. I believe the AA units (dti-pro, dti-pro32?) will set the scms flag to copies=infinite. I think this was an issue with DAT drives, I dunno. Not sure if the DIP does that as well...
There's also converters S/PDIF toslink or coax that convert to and/or from aes/ebu over xlr. Check out a pro audio place like fullcompass.com .