The early, pre 1975 or so, 660 and 850 CFM center squirter tunnel ram carbs. had what your looking for Probably not available new anymore
Nope. Center squirters only have one pump. BUT they did also make a 750 double pumper tunnelram carb with side hung floats. I don't remember the list number.
In theory, there is no difference between theory and practice. In practice, there is.