Looks like that is a Simpson Sears Elgin 2 with a Tecumseh engine
i was looking around ebay and found an outboard thats built almost the same. The lower units look identical besides the one on ebay looks really old. The link is http://cgi.ebay.com/ebaymotors/SEAR...at_Parts_Accessories_Gear&hash=item33624bfb3b It is a sears gamefisher 3 HP.