The Old Town canoe with serial number 58521 is a 17 foot long, CS grade, Otca model with Western red cedar planking, open spruce gunwales, 20 inch birch decks, birch trim, a keel and outside stems. It was built between January and March, 1920. The original exterior paint color was Yale blue. See
http://forums.wcha.org/showthread.php?t=418 for more information about this color. It shipped on April 7th, 1920 to Riverside(?), Illinois. A scanned copy of this build record can be found by following the link behind the attached thumbnail image below.
This scan was created with substantial grants from the Wooden Canoe Heritage Association (WCHA) and others as you probably know well. 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 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.
It is 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.
Benson