Hailey Welch -- who's NSFW street interview catapulted her into the internet stratosphere -- partnered with Fathead Threads in the aftermath of going viral, and they've plastered her lubricated phrase on everything.

Now, the company's owner Jason Poteete told Rolling Stone they've sold approximately 2,000 hats so far -- the cheapest of which is retailing at $32.78. They've already sold out of a signed version they were selling for $50.

It's easy to do the math ... even at the cheapest value, the company's pulled in a touch over $65k -- more than a little spit in the wind, we gotta say.

Unclear what Hailey's cut of that revenue is, but ya gotta imagine she's making a couple of bucks ... which is good news for her, because Hollywood's not breaking down her door just yet ... like some people originally thought.

We broke the story ... famed talent agency UTA has not signed to rep Hailey off the back of her viral success, as some outlets had claimed. In fact, she's kept a pretty low profile outside of the lucrative branding deal.

Poteete even told Rolling Stone he doesn't think Hailey's fully accepted her fame ... asking him not to share any personal details about her life or feature her face on merch.