A typewriter ribbon can be found at many places in stores as well as online. One place that sells typewriter ribbons online and in stores is Office-depot.
The typewriter ribbon is the store of ink for the typewriter. When a typewriter key is pushed the letter springs up and hits the ribbon - pushing the ink onto the page in the shape of the letter.
Typewritter ribbon can usually be found in stores such as OfficeMax, local typewriter supply companies, and many small, local shops within a person's location.
I'm not sure about your exact typewriter, but about 95% of typewriters use a standard 1/2 inch ribbon, there are many places that sell them online, a reliable one is shown below.
How do you change the typewriter ribbon of a Smith Corona 1940?
The best site to purchase Smith Corona typewriter ribbon (considering price and reliability) is via Ebay. The typewriter ribbon can also be bought on TigerDirect.
Abilene Typewriter Sales and Repairs, 1405 South 1st Street, Abilene, Texas.
www.FJAproducts.com has just about every typewriter ribbon, Time Clock Ribbon and Cash Register ribbon ever made. Flat rate shipping of 4.95. Toll free in the USA 800-982-9989
There are lot of types of typewriter ribbons present in the patent database.
Product ID: BR277 universal ribbon
Some words you can use with "typewriter" are keyboard, ribbon, keys, and vintage.
Open the cover, push the red lever on the right hand side of the ribbon towards the front of the typewriter, and lift the old ribbon off, replace with new ribbon, pull the lever back towards the keyboard and close the lid.
Typewriter ribbons can be found on Amazon, EBay, and online at typewriter supply stores. Online Typewriter stores will have the largest selection so that the correct size can be found.