I had this dropped off for a service, and I seem to recall a thread about someone not having seen a Briggs 2 stroke engine. Fuel mix is 50:1. I've worked on a couple of these before, and this one is missing a black plastic, semi circular shroud from above the spark plug. Excuse the blotchy look on the plastics, still a little wet in the pics.
The base is a Granberg Parksman, from Hawthorn Vic. Interesting in that the pressing is stainless steel, and is a 20 inch cut.