Old Town 143783 is an 18 foot CS (common sense) grade HW model canoe completed from February to April of 1946. It has open spruce gunwales, ash decks, thwarts, and seat frames and was fitted with a keel. It was originally painted dark green, and was shipped to Gardiner, Maine, on May 2, 1946.
Old Town canoes of this time period may still have had the slat seats of the wartime canoes... seems to me they didn't get back to using cane until 1947 or so. But people sometimes replaced the slat seats with cane seats once they became available.
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.