I did this once with a vintage Chanel flap. I went to the CBSA office at Pearson and told them I inherited the bag from my aunt and that there is no receipt. They wanted to see proof of this in the form of a will. I kind of looked at him like WTF. Who carries copies of their will, nevermind someone else's will around with them while travelling? Anywase, he still "let it slide this time." I got a green card that was stmaped and signed by the customs officer. I had to write the serial number of the bag on it and he looked inside the bag to verify it. However, they caution you that that card is only valid the first time around, and might not be considered valid for future travels. As well, I inquired about the sticker for a Longchamp bag my aunt had given me and they said that they dont do that. They can only issue the card if there is a serial number already attached to the item in question.