We put this one in the tech pages, but for an SBC I suggest the dynomax ones listed.
The ones you want are 3/4 length for a Chevelle for SBC.
This is the PN for the black coated ones: WLK-85118
This is the PN for the ceramic coated ones: WLK-86118
For something not as loud but with a good tone, I like Dynomax Super Turbos or Maganflows, or the Street Flows by Pypes.