Dan, I suppose I should have asked you about the forms long ago, how they got to Oburg and how mine got to Pdam, what you know about that?
So far, all we have to go by is the brochure that I attached to an earlier post in this thread. I have not yet found anything else archiva-wise, but there is a lot of searching to do yet. The tagged St.LBW canoes do have the right shape and many of the right characteristics to support this.
It is not a reach to see how an established firm only what - 15 miles away? might see an opportunity to add to their product line. It is not as far as when Joseph Leyare up and left Clayton with the St. Lawrence River Skiff Canoe and Steam Launch Company when it moved to Ogdensburg and was renamed Spalding St. Lawrence in 1895. Leyare bought the company outright in 1905 and renamed it Leyare Boat Works. In 1913, he closed the firm and shuffled off to Buffalo. When he returned to O-burg in 1917, he founded St. Lawrence Boat Works.
Interestingly, Spalding St. Lawrence issued a catalog for their canvas covered canoes in 1900. These were made to the same designs as their all-wood canoes, though with wide, cedar ribs. As far as I know, no canvas canoe identified as a Spalding has turned up. Rollin had a St. Lawrence River Skiff, Canoe and Steam Lauch Co. canoe at Assembly a few years ago, but it is not clear if it was built as a canvas canoe originally, or an all-wood that was subsequently canvassed. In any case, Leyare returns to Ogdensburg to start up a new boatbuilding firm, the Rushton molds are available, and off they went, it appears. There are other canoes listed in the 1922 literature - two models built in either smooth-lap, hollow-and-round, or rib-and-batten. These appear to be similar in design to the Spalding canoes. It is as if the main catalog was printed, then the forms were purchased, and an extra flyer printed to advertise these.
Coincidentally, if we take associate the above brochure with the other materials accompanying it dated 1922, the "twenty-seven years experience" takes us back to 1895, when Spalding moved to Ogdensburg.
As to why we don't see many of these - Leyare was much better known for his bigger boats - St. Lawrence River Skiffs, skiff-puts, guide-boats (larger inboard power boats used by fishing guides on the River), the "Number Boats" (twenty one-design gentlemen's race boats, two of which were built for George Boldt of Boldt Castle), and so on. Also, there was a short-sharp eighteen month depression in the early twenties, and another milder one in the late twenties. As I alluded to in an earlier post, this is not really canoe country, and the local market at the time was geared more towards the skiffs and larger boats. Canoes were built along the St. Lawrence by several builders, but they were never built in any quantity it seems.