you are still looking at 350 cams. The 305 has the same piston speed as a 350 3.7 bore Vs a 4" bore of a 350. The math is different for a 305. I wish I could type a long winded explanation like Bogie. If you put an intake and headers on with the cam change then you can make power and sound good. Unfortunately 350s need bigger headers than a 305.
If you just want a poser cam that works get a semi custom. look for 220º duration. .390 lift AKA short track small engine lift rules cam. 104-106º exhaust needs to be 110ishº with 8º split. For fun use a 650 x Holley or similar