Briggs Engine ID Help

[jtdunn4life]

I have a Troy Bilt 12av556o711 push mower. Needs some parts for the Briggs engine but I can't ID the model number to search for parts. Found this stamped above the muffler:

5351 23:51 D20

Should this info point me in the right direction or is there another number I need to be looking for? Thanks!

 

[bertsmobile1]

Look sideways at the crank case behind the carburettor.
There will a series of numbers electro etched into the alloy.
This is how Chinese B & S engines are numbered.
There will also be a sticker with a bar code on it with the same number but they usually fall off very easily.