10 years or so ago I sent the aforementioned museum a list of freight cars I wanted photos of and they sent me back a letter telling me which ones they had.
They sent me photocopies of prints that they had for a very reasonable price ($0.25 each I think) and I ordered prints after eyeballing the photocopies. I was very happy with the prints.
I don't know if they still do this.
The reasons prints are so expensive from libraries compared to vendors like Bob's Photos is that they send the negatives out to be processed, the photo processor makes a profit, the museum takes a few bucks for themselves (not unreasonable to expect me to pay part of the salary of the person doing the research)and the customer indirectly pays for sending the negatives by insured mail.
I sent similar inquiries to other museums too. It's hard to believe that I found a couple dozen photos I was looking for in the Kline- Culotta book 10 years later. I'm still looking for photos!
