I have a 1978 volvo penta with a engine tag that says 280a #361. I believe its a 280 outdrive. I have water getting into the outdrive via the clamping ring due to corrosion around the 4 bolts that secure it. So I need a new clamping ring but the shop says volvo has stopped making them and they cannot find one. They say the part# is 839589 but the diagrams I have found lead me to believe it is 851265. Can someone point me in the right direction as to where to find a part like this if volvo has indeed stopped making a part. The outdrive has only 400 original hours so I would like to fix it. THANK YOU