Why not try to fix that model B. If "gas is pouring out of it" you have a float/needle & seat problem, or too much fuel pressure. Make sure the float does not have gas in it. Check the alignment so its not hanging on the bowl sides. Make sure there is no dirt in the needle & seat. Check the float level.
These carbs have been out for 70 years & have run millions of miles. They are not that bad.
George
