Railroad souvenirs and memorabilia are popular collectibles. Items from the Atchison, Topeka, and Santa Fe Railroad are especially desirable. You will need to research each item and be specific in detail. People collect railroad dishware, hardware, lanterns, patches, pins, souvenir spikes, buckets, flatware and more. If you are hoping to learn more in order to sell or simply understand what it is that you have there are many available sources.
You can find used books online including:
"Railroad Collectibles: An Illustrated Guide" by Stanley Baker (out of print but you can buy used)
"Dining on Rails" by Richard Luckin
"The Official Guide to Railroad Dining Car China" by Douglas McIntyre
"The Collector's Book of Railroadiana: A Complete Guide to Collectible Railroad Memorabilia and Antiques" by Stanley L. Baker and Virginia Brainard Kunz
Remember that any values suggested in an older book will not reflect current prices. There are also websites dedicated to railroad memorabilia including Railroadiana Online and the Railroad Collectors Association.
Railroad dishware is popular with collectors. Dishware was used in dining cars and station restaurants. Some pieces were marked for a specific railroad while others were not but may feature unique patterns specific to a particular railroad. The condition of dishware enhances its value.
Other collectibles like lanterns, hardware, and signs may show wear or rust, or normal deterioration due to age.
There are a lot of reproductions out there. Some are sold as souvenirs, others are passed off as authentic. Fakes included signage, hardware, and dishware. For example, 1876 timetables of the Atchison, Topeka, and Santa Fe were produced for the U. S. bicentennial in 1976 but have been offered as authentic in online auctions. So you need to learn how to spot an antique. Old signs are popular with collectors and many reproductions have been offered as actual old signage.
Attend a collectors' show in your area. Investigate, ask questions, and talk to dealers who can be very helpful. If you want to sell your old railroad items, you may do well with online auctions as they have a wide consumer base.