I'll jump in on this one...
175540 is a 17' Molitor delivered in Feb 1966 and had a mast seat & step, and a rudder. It was painted in design #46. It was returned to Old Town in July 1967 due to discoloration and pits on the deck, as indicated on the back of the build record. The build record is attached.
Scans of approximately 210,000 records 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. Please join WCHA or make a tax deductable contribution 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. If you are already a WCHA member, THANK YOU!
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.