Receipts from the transaction do not work as legal documents but can rather prove that you indeed purchased the boas within Canada and did not illegally import them. That is still by no means a way of verifying them as "Legal".
Although Canadian F & W generally do not practice the inspection or removal of CITES 1 animals that are privately owned by hobbyists, it is still within their powers to do so. There have been instances in the past that has proven it so.
Although I love Dums' and I've been trying to obtain legal animals for three years now I still cannot bring myself to purchase any without legal paperwork. Itís too much of a risk to add such animals to my collection and I feel that supporting the sale of these animals is almost as negative as collecting them from Madagascar. Again, I feel there is a certain amount of responsibility here.
Don't get me wrong, people have their own right to make a choice with what they feel is right and wrong. I just lean against it. That's IMO...
Best of luck Jeff and she is a beautiful female indeed!