The 4x4 one superceded the original 2wd one - there are extremely rare now. You'll need the new 4x4 pipe to suit as well I'm afraid.
Here's a 2wd one - somewhat used...
http://cgi.ebay.co.uk/3dr-sierra-cos...item27aece7120
and a 4x4 new one...
http://cgi.ebay.co.uk/SIERRA-COSWORT...item20ae41ec8b
and hose
http://cgi.ebay.co.uk/SIERRA-COSWORT...item1e59bf2ca5