As evidence for my claim that in 1850 steel pens were common, I present a few ads from one day's issue of the New York Evening Post in 1844.
First ad for Lambert & Lane, Stationers.
Perry, Gillott, Windle and Mosely were british Manufacturers.
Wright was an American manufacturer, made in NYC but also sold widely
Hayden was an American manufacturer based in western Massachusetts (my article on Josiah Hayden comes out this month in the latest issue of The Pennant, from the Pen Collectors of America /plug)
Second Ad
Charles Cushing Wright was a famous engraver, sculptor of medallions and die sinks to make coins, who also made steel pens for a short time. (and will be the subject of my next article coming out early next year) His partner, J. C. Barnet, was a publisher (co-published the newspaper "The Age"), an entrepreneur and eventually became the treasurer of the Burton Theater, the first high-class theater on Broadway.
Third ad
A set of ads for Gillott pens from their American distributor, Henry Jessop. Also an ad for a new shipment of Russian quills to David Felt. Russia was one of the top producers of quills, along with Holland and Germany. And the uppermost ad is for Levi Brown's gold pens. Levi Brown was the first commercial producer of gold pens tipped with the new process ensuring the iridium tips stayed on.
For the last ad, I wanted to show that it was not just New York City where you could find steel pens. This is from 1839 in Kentucky, still considered, to some degree, the wild west. Louisville had only become an incorporated town 11 years earlier, and the wild forests came right up to the city limits. It was really only a city because of early river boat trade along the Ohio River. It had a population of less than 10,000 people, yet, you could buy steel pens from Perry, and Gillott, including Perry's India Rubber pens, as well as pens made by Charles Atwood, an early American pen pioneer from New England. You could use these pens with the famous ink from England, Stephens' Writing Fluid.
So, it's not at all far-fetched to see steel pens being used in 1850. It would have been more unusual to see quills still being used. It was mainly folks way out away from towns, as well as very old-fashioned establishments where you still found them. (But even the Bank of England was starting to transition over to steel pens by this point)
Thus, endeth the lesson.