That s/n comes up as:
35 350 2-cyl 2487558 2874703 1969 USA
From here:
http://www.marinshopen.se/Motorer/O...Mercury2takt3cyl2555hp/tabid/485/Default.aspx
It is a model:
1350109 MERCURY 1969 35
Parts listing:
http://www.crowleymarine.com/mercury-outboard/435.cfm
Gerry