The carb # is 7028262 with an M7 & VC under that.
I found a kit but it's special order and is going to take a couple days to get.
My reference book lists it for the full size 1968 400CI, 340 HP, OR the 350 HP engine.
The M7 is the date. If a Carter made Q-jet, the M=December and the 7 would indicate 1967. I believe the VC is the plant code, ie the Pontiac factory code used for ID just like the engine ID and was found on the factory build sheet during assembly.