I wish you luck. Barlows can be notoriously difficult to track down information on. A lot of manufacturers made that style of knife (and similar designs, like the electrician's knife). They were one of the more popular budget knives of their day. All the hardware stores sold them and all the guys that worked in the construction trade had at least one.

That being said, I still have my grandfather's and father's barlows and knowing their humble origin doesn't make them any less valuable to me.