You can get a fan bearing bracket on this site:
http://catalog.eautopartscatalog.com/mercedesshop/sophio/wizard.jsp?partner=mercedesshop&clientid=catalog.mercedesshop&baseurl=http://catalog.peachparts.com/&cookieid=1FX0MB1RS1IO0LFXSQ&year=1989&make=MB&model=300-E-002&category=G&part=Fan+Clutch+Bearing+Brkt
For about half that price... but you will need your engine #... If you call your dealer with your vin# they can give you your engine #.
I replaced mine recently and yes there are differences. It seems the engines were built before the cars so some earlier cars may have a later engine # in the series after the design was altered. If you buy a used part you need to get the engine # of the car it came from... or get the vin # and call the dealer again to get it's engine #.
Good luck.