The Rochester number which you posted is not a valid carburetor identification number. It is probably a raised casting number. Should you need to go this route (and the carburetor tag is missing), send me emails (1 picture per email) with the following shots:

(A) a shot of the throttle arm
(B) a shot of the side of the carburetor showing the choke housing
(C) a shot of the bottom of the carburetor with dimensions of the throttle bores
(D) a shot of the accelerator pump with the overall length
(E) a measurement of the inside diameter of the accelerator pump well (inside the carb) taken in the lower third (the non-tapered area) of the well.

Then call during normal business hours.

Jon.

Good carburetion is fuelish hot air
The most expensive carburetor is the wrong one you attempt to modify.
If you truly believe "one size fits all," try walking a mile in your spouse's shoes!
The Carburetor Shop