I believe summit carries one. If you cant find it there, around me there is a local speed shop that sold me one for my edelbrock carb set up. It was made and marketed by them and it was cheap. I think about 10 bucks. If you need one, email me and Ill pick one up for you. Email me at ajmdld@optonline.net
I have an edelbrock performer manifold and edelbrock carb and it works fine.