A shorter slot drive that the 106S would be good. I have several 106S drives, and they are long leaving only a couple of inches clearance in the rear for cables. The volume know is present. In Europe these drives come in silver color to match aluminum cases. I painted mine silver with red lips.
The 120S is available at Newegg for less than $41 w/free shipping. The common knock in the reviews is, the CD insertion and "swallowing" is not as easy as the 106S - maybe due to the shortened chassis? But there are several complaints about that. Also - the mini-CDs and business card CDs cannot be inserted unless someone invents some sort of carrier or caddy that makes them look like regular CDs.
Ideas?