Ayn Rand at her typewriter, in an undated photo (do you know the date?).
Contrary to a popular myth, Rand did not take her name from the typewriter. From the website of the Ayn Rand Institute:
What is the origin of “Rand”?
[From ARI’s monthly newsletter Impact, 06/2000]
“Ayn Rand, born Alisa Rosenbaum, based her professional first name on a Finnish one [see above]. The source of her last name, however, has been a mystery.
“Although its origin is still uncertain, recent biographical research by Drs. Allan Gotthelf and Michael Berliner has eliminated one possible source. An oft-repeated story claims that Ayn Rand took her last name from her Remington Rand typewriter while she was living in Chicago in 1926. This is false and we would like to put the error to rest.
“While still in Russia, c. 1925, and long before Remington-Rand typewriters were produced, Alisa Rosenbaum had adopted the name ‘Rand.’ Letters written in 1926 from Ayn Rand’s family in Russia already refer to the name ‘Rand.’ These were sent from Russia before Ayn Rand had communicated from America. The Remington and Rand companies did not merge until 1927; ‘Rand’ did not appear on their (or any) typewriters until the early 1930s.
“One lead to the actual source of the name comes from Ayn Rand herself. In 1936, she told the New York Evening Post that ‘Rand is an abbreviation of my Russian surname.’ Originally, we thought that this was a red herring in order to protect her family from the Soviet authorities.
“In 1997 Dr. Berliner noted an interesting coincidence when looking at a copy of Miss Rand’s 1924 university diploma. On the diploma was the name Rosenbaum in the Cyrillic alphabet:
The last three letters clearly look like the Roman letters ‘ayn.’ Richard Ralston then noticed that by covering those letters—and dropping out the second and fourth letters—what remains bears a strong resemblance to the Roman letters ‘Rand.’
“Although far from certain, it appears that the quote in the New York Evening Post may not have been a decoy.”
Her most often used typewriter was a Remington, I’ve read (but can’t find a reference now that I need it). So far as I have found, however, typewriters were always manufactured under the “Remington” marque, and never as “Remington-Rand.” Contrary to the implications from the ARI, Remington typewriters were produced from Reconstruction times (circa 1870), originally by the Remington Arms company. Typewriter manufacturing was spun off from the arms producer in 1886; that company merged with Rand, forming Remington-Rand in 1927.