As someone who worked pretty closely with Stevie (and was forwarded all of his emails from eMachineShop, etc), it can be pretty darn hard to detect when someone is scamming you. In the Stevie case, he had actually placed an order with eMachineShop. He had confirmation emails from them (real ones), order numbers (real ones), and was actually going through the purchase process.
Point is - he presented himself in a way that was every bit as legitimate and verifiable as you have. So it's not a reflection on
you that people are cautious here. We've just been burned before.
So it's probably not a horrible idea to have a vet handle this transaction.
Though it's a big huge piss-off for me, because FOR ONCE I was looking forward to getting my package of goodies on time, instead of 2 weeks after everyone else!
And I suppose while we're on that topic it's worth mentioning that I'd be a bad person to lend my hand this time to organizing things / shipping. Eerily, for the exact same reason I didn't run the focus knob groupbuy myself last year (the one that Steevie took over and scammed us through). I've got another cross country move coming up at the end of April / beginning of May. That's probably smack dab in the middle of when these would be arriving.
So, sadly, I think this should probably be handed off to a vet - and that's going to imply someone in the US
That said, I personally don't care if my particular order is handled by AnthoT along with any other Canadian orders.
If it doesn't dramatically increase the price to have him do the Canadian orders, and a US vet do the US orders, I'd gladly take that "risk" for the potential benefit of actually having these things arrive quickly 
and DTR will obviously still be great with the shipping and handling