The Old Town canoe with serial number 174085 is a 17 foot long Otca model with half ribs, a keel, narrow 2 3/4 inch planking, and a bang plate along the full length of the keel. It was built between July, 1964 and March, 1965. The original exterior paint color was dark green. It shipped on March 12th, 1965 to Cleveland, Ohio.
The Old Town canoe with serial number 150438 is a 16 foot long, CS (common sense or middle) grade, Yankee model with white Maine cedar planking, open spruce gunwales, a keel, and outside stems. It was built Between March, 1948 and March, 1949. The original exterior paint design was similar to the one shown at
http://www.wcha.org/catalogs/old-town/designs/design37.gif which was known as the design number 37. It was shipped on April 1st, 1949 to the Stroudsburg, Penna.
Scans 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 as you probably know well. 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 renew your membership 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.html to renew.
It is possible that you could have another number or manufacturer if these descriptions don't match your canoes. Feel free to reply here if you have any other questions.
Benson