Rebuild the Quadrajunk or replace

[my67c20]

Well after getting 6 miles per gallon for way too long and constantly smelling gas i have decided to attack the carb. My question is should i rebuild the quad or replace? If i replace i would also like to do the intake as well. Reduce a bit of weight and pick up a few tenth of a mile. Second question is were can i get a good but yet low cost <$500 carb and manifold bolt on kit? Thanks in advance for any suggestions. Oh by the way i have a 350.