The Old Town canoe with serial number 43871 is an 18 foot, CS (Common Sense or middle) grade, HW (Heavy Water) model with red Western cedar planking, closed spruce gunwales, birch decks, birch trim, and a keel. It was built between June and July, 1916. The original exterior paint color was palm greeen. It shipped on August 3rd, 1916 to Center Harbor, New Hampshire. The back side of the card shows that it returned for repairs in 1926 and 1934. Scans showing both sides of this build record can be found by following the links at the thumbnail images attached below.
These scans and several hundred thousand more were created with substantial grants from the Wooden Canoe Heritage Association (WCHA) and others as you probably know well. 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 will join or renew your membership to 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 join.
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.