Summit lists 8 cylinder heads for a 77 360 and 471 heads for a 77 350. That is almost 59 to 1 ratio, there is not that big a difference in the number of cars out there so there has to be room for a new head or two. Oh and the 77 302 has 202 heads on summit. If they can justify the wattered down sales caused by 471 different SBC heads surely they can justify a couple more SBM heads, maybe give us 10 to pick from