Old Town 172030 is a 20 foot guide model, finished between April and June of 1962. It has half ribs and a keel and was painted pale blue, then was shipped to Walle's Nursery and Landscaping Service in Flat Rock, MI on June 18, 1962. The reverse side of the record indicates an inquiry from someone in Grand Rapids on June 16, 1978.
Scans of this record are attached below-- click on them to get a larger image. This scan and several hundred thousand others 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/ot_records/ if you want more details.
It is also possible that you could have another number or manufacturer if this description don't match your canoe. Feel free to reply here if you have any other questions.