1,015 is the total number of MN [822] and MO [193] L72 engines Tonawanda built for the 1969 model year.
For 1965 there were 2,304 "IF" 396/425 Corvette engines built but only 2,157 396 Corvettes produced, an installation rate of 94%. Applying that to L72s puts the production figure around 954.
Since the 198 or so Yenkos are known the question has always centered around the number of non-Yenko COPO Camaros built. Having regularly walked the pit area at drag meets I know there are many heavily modified '69 Camaro drag cars out there with no paperwork and non-OE drivetrains. Missing cowl & VIN tags are common; some of these have been raced since new and could have easily been COPOs.