The closest match in the 1x6087 range is 18 feet long. The Old Town canoe with serial number 116087 is an 18 foot long, CS (common sense or middle) grade, special square end paddling model with red Western cedar planking, open spruce gunwales, oak decks, oak thwarts, oak seats, half ribs, a keel, outside stems, a floor rack, sponsons, a rowing seat, and rowlocks. It was built between June and December, 1935. The original exterior paint color was dark green. It shipped on February, 25th, 1936 to Fort Wayne, Indiana. A scan showing this build record can be found by following the link at the attached thumbnail image below.
This scan 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/catalogs/old-town/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/about-wcha to learn more about the WCHA and
http://www.wcha.org/store/membership to renew.
It is also possible that you could have another number or manufacturer if this description doesn't match your canoe. Please attach some pictures of the numbers and confirm the length. There should also be a serial number on the inside stem which might be easier to read. Feel free to reply here if you have any other questions.
Benson