The Meghan Markle Effect Has Landed! The Accessories She Wore for Her Debut With Prince Harry Are Already Sold Out

She might be a relative newcomer in royal circles but Prince Harry‘s girlfriend Meghan Markle is already quite the style influencer.

Since she publicly stepped into the limelight at the Invictus Games on Saturday, the brands Markle’s worn have experienced an unprecedented surge in sales (and publicity!). One such label feeling the “Meghan Effect” is sunglasses brand Finlay & Co., whose designs the actress wore as she sat side-by-side with Harry at a wheelchair tennis match on Monday. 

“The orders have been overwhelming,” co-founder David Lochhead tells PEOPLE, adding: “It was a total surprise. I was at dinner with my family on Monday night and had my phone in my pocket so it wasn’t until I checked my phone on the way home. I let out a little scream on the tube!” 

Despite having counted celebrities like Rihanna, Gigi Hadid and Jessica Alba among their clientele, Lochhead says he’s never experienced such a frenzy since the company launched in 2012: The website crashed twice and they sold $26,885 of stock in 24 hours. 

“We were straight onto our factory in Italy to see if they could speed up our current order and placed additional orders,” he says. “They are pulling out all of the stops!” 

The unisex Percy shades, which retail for $160 (and are also owned by Sienna Miller) were the perfect finishing touch for Markle’s low-key-yet-chic look for her appearance at the games on Monday, the first time the royal couple appeared together at an official event.

Wearing ripped jeans from Mother Denim, an oversized “husband shirt” by designer pal Misha Nonoo, the look was accessorized with dark tan leather Sarah Flint “Natalie” flats (currently sold out) and a matching tan tote bag by Angelina Jolie’s favorite, Everlane, (a leader in sustainable fashion) whose Day Market Tote is completely sold out in three of four colors, with stock not expected until Nov 25. The sunglasses have a waiting list of “hundreds” with stock not expected until at least the end of October. And Flint tells PEOPLE that though they don’t release sales data to the public, they did see an uptick in website traffic after Markle stepped out in the flats.

So what’s the sartorial appeal?

“I think she’s got amazing character and depth,” says Lochhead, clearly a fan himself. “She’s more than an actress, she’s a humanitarian and people seem to be able to relate to her.

“Meghan’s style is quite relaxed but it definitely has a polished edge,” adds Lochhead’s partner Dane Butler. “And she mixes high street with designer just like the Duchess of Cambridge.”

Flint agrees, telling PEOPLE: “Meghan has a very chic, yet approachable style that resonates with women worldwide, so it’s no surprise that women want to emulate her looks.”

And Markle isn’t the brand’s only royal link. Kate’s sister Pippa is also a fan of their styles, as is Zara Tindall. Might a royal warrant be in the cards one day?

“That would be great,” jokes Lochhead, “but maybe not just yet!”