It was made on 6 October 1976. The plant of origin is unclear since I can't read the digit that would originally have followed the 1 at the end of the Code.

The engine has a displacement of 32 cubic inches or 520 cc, making it one of the largest single cylinder engines. It is of the 6th design generation, and has a horizontal crankshaft, a mechanical governor, a Flo-Jet carburetor, and a belt drive. It has a flange mounting for whatever it drives (rather than engine and driven unit being mounted on a common base), ball main bearings, and a rope starter (not a recoil starter or electric starter). All in all it seems a quite unusual beast. At this point I don't know what the belt drive is for.

Here is the Illustrated Parts List for the engine:
http://bsintek.basco.com/BriggsDocumentDisplay/18nnALXAnfBhU7y.pdf

Here is the Operator's Manual:
http://bsintek.basco.com/BriggsDocumentDisplay/msowHM-K_ny7tH217FzoPu.pdf

Being pre-1982, it has breaker point ignition, but yours is of an odd type, using a plunger to operate points mounted externally on the engine, not inside the flywheel. It also has a large 2 piece Flo-Jet carburetor.

I suspect you will need to work on that one with the Briggs manual for pre-1984 engines close to hand.