These are not too rare, finding one with a good case that isn’t damaged is rare. You must be very careful not to damage the tip of the gearcase or the unit will not lock in the folded position. Yours looks to be a 1967 Johnson with the 90 degree higher thrust gearcase. The biggest concern is the condition of the fuel tank, make sure it isn’t rusted or fouled inside. Going through the ignition, fuel systems, impeller replacement is usually all they need to become reliable daily runners. These engines don’t have much compression, you will only see about 70PSI, which is normal.
I don’t know what other questions you have….
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