I suspect that at least one of the digits in this serial number may not be correct since the Old Town Canoe with serial number 128201 is a 16 foot long HW model that shipped to Florida. Let me know which digits are the least clear and I will post the correct build record. My guess is that you may have the Old Town canoe with serial number 128211 which is an 18 foot, GS grade, Guide's model with open spruce gunwales, ash decks, ash trim, and a keel. It was built between November, 1939 and February, 1940. The original exterior paint color was G. S. (Guide's Special) green. It shipped on April 23rd, 1940 to Duluth, Minnesota. A scan of this build record can be found by following the link at the thumbnail image attached below.
These scans were 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.
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.
I think you were correct with the 128291, but, just to be sure, could you do a quick check of 128281. After looking, I believe the only 2 numbers the 5th digit can be is either 8 or 9.
The Old Town Canoe with serial number 128281 is a 16 foot long HW model that shipped to Massachusetts. There are about ten canoes in the 1282xx range which are very similar to yours.