Any 318 head before the magnums arent worth the work. You want power for a daily vehicle, not racing, right. If you trust me, Get a set of magnums for a 318. They have the larger valves and install beehive springs from a series 2 GM v6. They drop on. This combination with the original cam will give you a large power/ torque increase from a small cam. Even a stock roller. Similar to a vortec heads swap on a 350. Hit the yard before it really starts to snow. You could probably get the magnum heads and GM beehive springs for under 250, and just clean them up with new 2.2L umbrella valve seals.
Read one for GM springs
Best head mod for a low budget mopar . Yes I did it. The good? ported 051 swirls flow about 175 on a good day.