Old school underhood superchargers...anyone remember?

The old MP catalog used to sell them in two different sizes. The larger one for the 360. I think it was a 177 and yes, it was a B&M. They still make those small superchargers but the manifold for them they do not.

If you want to use the little B&M, try contacting Dyers (IIRC) who will make the supercharged intake manifold for you. You’ll need to know what supercharger exactly you intend to use as well as exactly what head your going to use.