I use one in order for me to run two of the new wired remotes (one at the driver and one at the stern) and a cd changer at the same time. They are discontinued as you are probably already aware and there is no replacement as of yet that I know of, but there's one for sale right now on ebay with four days left to go (click on link).
XA-C30 (http://cgi.ebay.com/Sony-XA-C30-Sour...tegoryZ1498QQs sPageNameZWDVWQQrdZ1QQcmdZViewItem)