The term Arrowhead refers to the design of the decks. I'm not sure if the SN reflects anything about dates, etc. Dan Miller of Dragonfly Canoe Works has published some info on the Meramec Canoes and can be found at http://dragonflycanoe.com/id/
Hope this helps and when Dan sees this, he may have other info to help.
We have been compiling some records here in St. Louis. We have an Arrowhead serial #381, which according to info from the original owner was purchased in the '30s and possibly built in the 20's. Do you have measurements for your canoe and have any idea which model it might be? Gil Cramer in Ohio had information on a Meramec that was purchased from St. Louis in either '37 or '38, serial #1164. Ken Mueller has a Meramec serial #664or #564. I have attached a picture of ours. Hope others can do the same or share measurements and/or serial #s.
Wow. Great to hear from you. I will take some pictures and measurements and send them to you. The canoe is now hanging from my living room ceiling because I have no more room in my shop. I am looking forward to restoring this boat.
It is wonderful to maybe get some information about it.
Thank you so much.