Your canoe looks like the Old Town with serial number 115351 to me. This build record shows a 17 foot long, CS (Common Sense or middle) grade, HW (heavy water) model with red Western cedar planking, open spruce gunwales, ash decks, ash thwarts, ash seats, a keel, and sponsons. It was built between January and July, 1935. The original exterior paint color was dark green. It shipped on June, 22nd, 1936 to Von Lengerke & Antoinne in Chicago, Illinois as identified on the stern deck.
The build record for 5351 shows a 17 foot long, CS (Common Sense or middle) grade, Charles River model with closed spruce gunwales, spruce outside finish rails, ash decks, ash thwarts, ash seats, and a keel. It was built between October, 1906 and April, 1907. The original exterior paint color was dark red. It shipped on April, 22nd, 1907 to Walter Coleman & Sons in Providence, Rhode Island.
Scans showing both of these build records can be found by following the links at the attached thumbnail images below.
These scans and several hundred thousand more 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/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 join.
It is also possible that you could have another number or manufacturer if these descriptions don't match your canoe. Your canoe has diamond headed bolts which were not introduced until the early 1920s. The serial number font stamps were different in the early 1900s, especially the "3" digit. See the images below for some examples.
The specifications for the HW, Charles River, and Sponson models are shown at
http://www.wcha.org/catalogs/old-town/dimens-1.gif confirming that a 17 foot long canoe with sponsons is typically 42 inches wide and weighs 103 pounds. See
http://www.wcha.org/forums/index.php?threads/12416/ and
http://www.wcha.org/forums/index.php?threads/12320/ for examples of Charles River models from this era and the video below showing a 1946 HW with sponsons.
Feel free to reply here if you have any other questions.
Benson