I absolutely don't trust this, even if everything checks out. Maybe I'm just a pessimist, but my advice is DON'T DO IT. Greys are expensive, but worth the price you pay for security. With something like this where you can't meet the bird, it'd be easy to get scammed. Hell, if this person is a professional scammer, they may even have a fake vet website or separate cell phone #. Go to a local rescue, check Craigslist, go to a local breeder, hit up a petstore...
www.birdcrazy.com
That's where I got my Grey from, and (s)he was expensive, but completely worth it. They have three five-month-old babies right now and I've met all of them, they're so sweet. It's a local store, highly reputable, they purchase from trusted local breeders, all the babies are hand-raised, and the birds are handled every day, all day long. There are 2 others not listed on the site, not sure how old they are though.
Obviously there are more resources out there, I just wanted to pass along one I trust implicitly. You seem like you really hope this works out, but even if everything seems to check out, there are still ways scammers get your money. Many do this for a living with no other form of income, so they're incredibly skilled at it. BE CAREFUL.