VRI's are easier to obtain, assuming you can get someone to mentor you. Obtaining a copperhead is very straight forward, BUT, let me warn you, that the pending legislation will BAN all commercial breeding of copperheads, so that's not a valid reason for obtaining them. Second, no zoo really has a need for one, as there are scads of them out there already. Finally, you may not release them into the wild; it's a violation of NY state law as well as a bad idea, given that they can transmit zoonoses to other wild snake populations. Several people have wanted to re-introduce timber rattlesnakes for years, but its never been approved (more likely because of political backlash that the DEC would get from setting loose dozens of poisonous snakes----but the ignorance of the public, is a topic for another discussion).
As for ESPs, Tom is right...their tough as nails to get, unless you are using the snakes for educational or scientific reasons(venom study, etc.).
Find a mentor, then apply for the VRI for a copperhead. Also, get a Captive born southern. THey are prettier, and you are not pulling from the wild populations.
Matt