As a long time mid year 'Vette guy.... A '64 is just a "non starter" as 'Vettes go. Only reason I'd take a 64 would be as a body to build a Pro-touring car... So if that's your plan then the 64 would be the right car to do that with. Not trying to be mean spirited or anything here - just being honest. The '64 is the step child year - no split window - no big block - no disc brakes all around - no special racing credits - no ZO6 big tankers etc... it's just kind of a "year" without anything really going for it. The '65 saw some high horse small blocks and the first big blocks... the '63 had the split window and was the first of that body style... thus the '64 just is kind of stuck in between.
The only reason I'm saying this - or even bothering to have an opinion on your trade - is just so you know what you're 'getting'.
Good luck with which ever way you choose!