Vince,
I think the handles were done in house back then. Bone was shipped into Walden by the boxcar-full back in those days, in fifty pound burlap sacks like a sack of potatoes. I believe Schrade alone went through two carloads of bone per month! There are records of fires at each plant's handle making facilities over a period of years, most of which were caused by the dreaded spark igniting celluloid dust. Luckily those buildings were purposely made of brick and located away from the main plants. Napanoch, due to the location of its cutting rooms, wasn't so lucky.
Before the advent of jigging machines the old pick bone from Walden's (the town) knife manufacturers was extremely similar, NY Knife, Walden Knife Co., and Schrade Cut. all had nearly identical handles for a time, probaby due to the fact that the bone jiggers likely were trained similarly. Heck, in a town with three major cutlery companies located in a half mile radius, I'm sure there was a lot of "job relocation" going on over the decades. In fact, there was a shop called the Walden Cutlery Handle and Manufacturing Company that was a joint partnership between those very companies, formed to insure a steady supply of bone for the local industry, (although I think the partnership existed even before that company was formed). Schrade eventually bought the handle company out and absorbed it into its manufacturing facilities.
That's a fine example Vince, I've definitely got a soft spot for those old Waldens!
Eric