The Old Town canoe with serial number 180307 is a 17 foot long Otca model with a keel. It was built between March and April, 1968. The original exterior paint color was white. It shipped on April 22nd, 1968 to Downers Grove, Illinois. A scan of this build record can be found below.
This scan 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/ot_records/ if you want more details. I hope that you will donate, join or renew your membership to the WCHA so that services like this can continue. See
https://www.woodencanoe.org/about to learn more about the WCHA and
https://www.woodencanoe.org/shop to donate or join.
It is 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. Good luck,
Benson