I've not been able to find any indication that Clark Marine in Augusta, Maine or Moose Island Marine in Eastport, Maine were ever an Old Town boat dealer. You may want to contact them at
https://www.clarkmarinemaine.com/ or
http://www.mooseislandmarine.com/ to see if they might have any more information. The Guardian Safety Glass, the cleat from Wilcox, Crittenden & Co., and the key from Chicago Lock were all suppliers to Old Town and many other manufacturers so that doesn't narrow it down much. If your boat is an Old Town then it is most likely to be the one with serial number 169421 that shipped to the Belgrade Lakes on May 19th, 1961. The Evinrude motor may be from Clark Marine since the page at
https://www.clarkmarinemaine.com/our-history indicates that they started selling these in 1958.
The Old Town build record for serial number 169421 shows a 16 foot long Lapstrake 16 Fisherman model boat in AA (or top) grade with a keel, outside stems, and a floor rack. It was built in December, 1959. The original exterior color was white with a red copperpac (i.e. Woolsey Paint) bottom. The back side of the record indicates that it may have been in Mount Vernon, Maine during October of 1982 when there was a previous request for a copy of the build record. Scans of this build record and the others in the 16942x range that shipped to Maine and New York are attached at the links below.
These scans and several hundred thousand more 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/catalogs/old-town/records/ if you want more details. I hope that you will join or renew your membership to the WCHA so that services like this can continue. See
http://www.wcha.org/about-wcha to learn more about the WCHA and
http://www.wcha.org/store/membership to join.
It is also possible that you could have another number or manufacturer. Feel free to reply here if you have any other questions.
Benson