There were two different HP 'double hump' heads. Some were machined for 1.94" intake valve sizes, and were used on the 295/300 hp 327/350 engines, and others were machined for 2.02" intake valve sizes, and were used on the 350 hp engines (327s' used in Corvettes for 1967)... The casting numbers and external appearances of these heads were identical as installed, and all were called 'double hump' heads for the casting marks on the ends.
PS. Actually for torquey street engines, the smaller valve head is preferable (IMO)... the large valve sizes are only beneficial at very high rpms and high horsepower.