This looks like a great canoe. I'm very sorry to be responding so late but it has been a very busy summer. The Kennebec canoe with serial number 19906 is shown on pages 100 and 101 of volume four in the Kennebec ledgers. This was assigned to a 16 foot long Kennebec Model, type B. It was planked by Lanteigne(?) on October 13th, 1928. The canvas covering was applied by Soucier(?) on October 13th, 1928 who also applied the first filler coat on October 20th, 1928 and the second filler coat was on October 26th, 1928. It was railed by Thompson on June 14th, 1930. The original paint color was green. The shipping date was June 18th, 1930 to location "30-500". This location is probably an order number but we don't currently have enough information to identify it. The scans of this build record can be found by following the links at the attached thumbnail images below. These original Kennebec records are reproduced through the courtesy of the Maine State Museum.
The microfilms and scans of these records were created with substantial grants from the Wooden Canoe Heritage Association (WCHA). 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.php to join.
More information about this and other Kennebec models can be found in the Kennebec catalogs contained on the Historic Wood Canoe and Boat Company Catalog Collection CDs available from http://www.wcha.org/catalog/ and http://www.dragonflycanoe.com/cdrom.htm on the web.
It is also possible that you could have another number or manufacturer if this description doesn't match the canoe. Feel free to reply here if you have any other questions.