So I am thinking (through the help of Glenn's attached Kennebec 1910 catalogue, Benson's links to WCHA discussions, and my own research), that this is a 1910 "Charles River" model. Though it seems to be a rare model with its closed gunwales from the company's earliest days, the specs match at 15' long, 31" wide at the interior gunwales, and 12" deep, with an upswept bow and stern. Apparently it's about 58lbs, but honestly it feels a whole lot lighter than that (especially after wrestling with my new-to-me Royalex Soloed Penobscot 16 which is supposed to be the same weight).
From the 1910 catalogue that Glenn attached, this model is advertised as the "1915 Charles River". I wonder why they included "1915" in the title back in 1910?
Thank you all in this group for the continual inspiration...