It's often hard to find parts when rebuilding an old vehicle. You are usually limited to either high priced replacements or reasonably priced used parts that are less than stellar in quality.
The Athena gasket kit is the exception. I found that it includes most of the gaskets and o rings necessary for a complete engine rebuild of my 78 Suzuki GS550. The only missing item was the o ring in the oil sump area.
The gaskets themselves are well made, not too flimsy, but of good thickness and quality.
Didn't include the "half moon rubber seals" and the valve cover gasket had 1 bolt hole in the wrong place....and yes I did flip the gasket in every way possible but 1 bolt hole would not line up.