you will find ysk on alot of honda parts, it is a casting company that makes parts for honda (and other companies) I have seen ysk stamped on water and oil pumps, and probably other stuff too.
as far as the 2, I dunno what that is.
if you are looking for a tranny ID look on the front toward the top of the bell housing you will see 3 digits in black letters/numbers (eg. s80, ys1, s40, etc)