It looks like maybe your customer should double check the serial #. 7442 in the Old Town build records was issued to a 17', AA grade CR (Charles River) model with long mahogany decks and two flag poles and sockets, originaly painted a dark green. This canoe has double mahogany gunwales and no sponsons that I can see.
The scan of this record is attached below-- click on it to get a larger image. This scan and several hundred thousand others were created with substantial grants from the Wooden Canoe Heritage Association (WCHA) and others. A description of the project to preserve these records is available at http://www.wcha.org/ot_records/ if you want more details. I hope that you and anyone else reading this will join or renew membership in the WCHA so that services like this can continue. See http://www.wcha.org/wcha/ to learn more about the WCHA and http://www.wcha.org/join.php to renew.
It is also possible that you could have another number or manufacturer if this description doesn't match your canoe. Feel free to reply here if you have any other questions.