Yeah, the seven is more along the lines of a solex. Made to be slow on purpose.
Luckily it does have av7 cases. If I were you I'd get an av7 cylinder and Piston, 15mm intake, sha 15 carb and a standard av7 pipe. Correct carb jets.
Basically, you'll be spending all the money to make a 45mph 50v to get a 30mph 7.