It's a Monky Ward SeaKing. They were made by OMC Gale Division up to the early 1970's, when they switched to Chrysler Marine for manufacture. They went out of business in 1984 when Chrysler sold the marine division.
Yours was made between 1974 and 1977. Maintenance parts should still be available, but items like cowls, tiller handles, etc. are long gone. Not a popular motor in the first place, so not a lot of used ones laying around either.
Google "Laing's Outboards" for parts availability.
