The 400-series cars were - as you found - PS-1’s that NYSW purchased in the late 1940’s. In the early 60’s, the railroad sold all but two of them (401 and 402) to the Monon. To replace them, they purchased a group of 40’ boxcars from the Lehigh Valley (oddly, the replacement cars were built in 1926, which made them significantly older than the cars they replaced - I don’t get that decision). Those cars were numbered in the 500-series and many of them were repainted into the green Susie-Q scheme.Although the boxcar body style on the model is fairly close to the car in the photo, there are differences in the side sill, but it's a better choice than the usual AAR 40-foot car. The Walthers model gets the green color and the Susie-Q figure right, but the style of lettering for the Susquehanna road name differs from the photo.
The Susie-Q lettering would have come after my one trip to Butler. According to Wikipedia, Ford closeds its Edgewater Assembly Plant in 1955, which cost the NYS&W one of their primary sources of traffic. 1961, real-estate developer and millionaire Irving Maidman purchased the Ford plant for use as a rental warehouse, and he eventually purchased an Alcoa plant for the same purpose.
In October 1962, Maidman purchased the NYS&W to ensure their freight operations in Edgewater remained active, and he began arranging for the railroad to lease some property in Edgewater for backup storage. I've seen elsewhere that the Susie-Q paint scheme was the result of a Maidman-sponsored employee contest. However, traffic on the Edgewater Branch continued to decline, and the Susquehanna declared bankruptcy in 1976. In 1980, the NYS&W was sold to the Delaware Otsego Corporation, which began ther road's revival.








