79 360 cam selection

mill the heads, or if the budget allows...buy some new heads with smaller chambers-RHS LA-X
On the cam, well thats gonna get 20 diff answers, one will be the comp 268* hyd cam, another could be the the comp solid 268/274* .488/.501 lift 110cl 230/236*@.050, you'd need adjustable rockers with the solid, those can be cheap or expensive depending on the style/brand, but easily had.

http://www.summitracing.com/parts/CCA-20-233-4/