Tommy,
I bought a complete smog system for my '68 L35 car a few years ago from Bill Hodel. In my opinion, he is the "go-to" guy in the country for smog systems and parts. He supplied me with everything....date coded pump, pulley's, hoses, dated coded clamps, nuts and bolts....i.e. everything. His info is below:
Bill Hodel
8257 Oxford Chase Circle N.W.
Massillon, Ohio 44646
Phone: 330-832-0871
e-mail: billhodel@sbcglobal.net
Here are a few pictures of the bolts you're after and what it looks like on my engine.
Bob
PS: Not sure why the pics are sideways!