I was interested in the following sentence which appeared in an article titled “HORSE MARKET" in The New York Times (Dec. 4, 1861).

There is several first-class draught horses in market, held at $150@$175 each; very slow sales.

Can someone clarify if the fragment "There is several first-class draught horses in market" is ungrammatical, as I think it is?

As the sentence is dated on 1861, perhaps the grammatical rules governing this form are changed meantime. Are they?

However, nowadays, I would reword "is" with "are", but I'm not sure on this correction because the presence of the word "several" confuses me.

(Apologize in advanced if the question is not good for this site. If so, please delete it. Thank you.)