Blue Book of Gun Values
One can find more information about Davidson basketball by going to the Davidson website. The website has information about all of its sports, including basketball.
Someone can find information about Harley Davidson patches by asking a person who has Harley Davidson patches. They could also go to the library and find a book about Harley Davidson patches.
UMC refers to Union Metallic Cartridge company. They are owned by Remington and only make ammunition not firearms.
You can find information on websites such as Amazon; there you can get reviews about the hard-hats' durability and quality. You can also find more information, such as prices, and more about Harley Davidson, at the Harley Davidson website.
Marlin Firearms: A History of the Guns and the Company That Made Them by William S. Brophy
Information about Harley Davidson motorbikes can be found on the Harley-Davidson website. Alternatively, motorcycle magazines or websites may contain articles about Harley Davidson motorcycles.
National Firearms Company was a trade name used by Hopkins & Allen @ 1900.
Not much information is available on Meriden Firearms, but you might go to the library and locate Flayderman's Guide to Antique American Firearms. Then look through all the books on that shelf. The Meriden company was set up by Sears Roebuck to manufacture firearms for sale through their catalog and retail stores. It lasted from about 1905 to 1915.
Firearms marked Hartford were manufactured by Crescent Firearms for the Simmons Hardware Company of St Louis c. 1890-1930.
Eastern Arms Company was a trade name used by Sears Roebuck. The guns were manufactured by Meriden Arms, Iver Johnson, Stevens, Savage, and probably others.
Information about Harley Davidson rims can be found several places. Probably the best place would be a Harley Davidson outlet, or a store that specializes in motorcycles and their equipment.