The Old Town canoe with serial number 33724 is an 18 foot long, AA grade, Ideal model with red Western cedar planking, open mahogany gunwales, 30 inch mahogany decks, mahogany trim, half ribs, and a keel. It was built between August, 1914 and February, 1915. The original exterior paint color was dark red. It shipped on April 6th, 1915 to Saint Paul, Minn. A scan of this build record can be found by following the link behind the attached thumbnail image below.
This scan and several hundred thousand others were created with substantial grants from the Wooden Canoe Heritage Association (WCHA) and others. Additional information about the project to preserve these records is available at
http://www.wcha.org/catalogs/old-town/records/ if you want more details. I hope that you or your father will join or contribute 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.html to join.
The canoe with serial number 33721 is 17 feet long so that is probably not yours. It is also possible that you could have another number or manufacturer if this description don't match your canoe. Feel free to reply here if you have any other questions. Good luck with the restoration.
Benson