What carb is this? What are my options?

Hey guys,
new to the forum, and relatively new to Mopar (my other Mopar was a 51 Plymouth Concord with a 218 flathead six).

I've got a 64 Barracuda, original /6 car, but the PO swapped in a 273.
My question is, what carb is this on the car? Looks like a 2 bbl, but make/model?

What are my options as far as moving up to a 4bbl/intake/ headers on this engine?

Thanks!