The phrase "a sort of folk" is correct and usable in written English.
It can be used to describe a type or category of people, often in a general or informal context.
Example: "The festival attracted a sort of folk who appreciate traditional music and art."
Alternatives: "a kind of people" or "a type of crowd".
A sort of folk pop, as it turned out.
"It's a sort of folk theater tradition brought up to date".
He didn't seem to be bothering anyone and became a sort of folk hero in the area.
Mr. Erdogan has become a sort of folk hero in the Arab world for his open challenges to the government of Prime Minister Benjamin Netanyahu.
The New Yorker, October 10, 1977 P. 112 U.S. JOURNAL: MAINE about Marshall J. Dodge III, who is a sort of folk hero in the State of Maine.
She is exalted in small towns across the country as a sort of folk hero, a protector of traditional values; her beauty queens were once congratulated by ministers and received by heads of state.
He has in essence, achieved a sort of folk-hero status; on Wednesday, his just-created Twitter account hit a million followers, setting a Guinness World Record.
Except in the final piece and an encore, when they collaborated on a pair of Bartok's Romanian Folk Dances, Mr. Schiff and Muzsikas shared the stage but performed separately, in a sort of folk-classical dialogue.
Halfway through his electrifying new memoir, "Life," Keith Richards writes about the consequences of fame: the nearly complete loss of privacy and the weirdness of being mythologized by fans as a sort of folk-hero renegade.
They are from Algeria and play a sort of classic folk and are very lively.
At least that's what their letters to the editor indicated, and, unlike Mr. Pollard, I not only retained my job, but also came to be regarded (if you'll forgive a bit of immodesty) as a sort of newsroom folk hero.
