The phrase "a sort of first" is correct and usable in written English.
It can be used to describe something that is a preliminary or initial version of something else, often implying that it is not fully developed or complete.
Example: "This prototype is a sort of first attempt at creating a more efficient engine."
Alternatives: "a kind of initial" or "a type of preliminary".
One of these, "Winter Dreams", he later described as "a sort of first draft of the Gatsby idea".
He also became an amateur painter, and he later recalled, as a sort of first impulse toward abstraction, an adolescent conviction that each colour had a mysterious life of its own.
The interviewer asked whether "the anti-Nazi films of the nineteen-forties were motivated by the desire to fight the enemy, a sort of first degree that a reworking of a genre would risk breaking".
He then became, in effect, the third member of a strange triangular relationship that installed Magda at the Führer's side as a sort of first lady of National Socialism.
Perhaps this is partly to do with Professor Farruh Yilmaz's observation that the far right gained a sort of "first mover advantage" by claiming ownership of the immigration debate in Europe.
Managing Downton Abbey?" The family seat is turned into a convalescent home as Thomas reinvents himself as a sort of first world war male version of Kerry Weaver in ER (complete with "sexual outsider" back story and physical disability).
So perhaps Crouch's concept of "the guide" offers us a sort-of third way, one in which theatre makers don't have to make a brutal and sometimes impossible choice between pandering and patronising.
It's been called bad because it appears to be a truncated, unauthorized version of the play-a sort of seventeenth-century bootleg.
Now I'm in the game, a sort of first-person sci-fi shooter.
Ms. Chlumsky turns up as a sort of third point in a semi-romantic triangle.
That night I was on a sort of second-line "anything else" kind of alert.
