I actually am guilty of having an 'ESKA Toss' many years ago at a Lake Catherine wet meet because it was the only motor that would not anger one of our members when we threw one into the lake (not to worry, we had a rope on each motor and did not leave them in the lake). This forum is probably not the best source for information on the ESKA outboard because nobody that I know collects the Tecumseh powered air-cooled motors from ESKA.

The last company that I dealt with that had manuals and parts for the ESKA outboard was Certified Parts Corporation in Janesville, Wisconsin.

Rated at 5hp, it is an air-cooled motor however, if it is similar to some I have worked on in the past, there is still a water pump impeller in the lower end that pushes water to the bottom of the powerhead to condense gases and to keep heat from building up under the top cowlings. I am not an expert on your outboard, but I am fairly certain that it is an ESKA outboard manufactured in 1974 for Sears in Canada.