Meghan Markle's $319 striped dress is sold out — but we found 10 dupes from $30

Aug. 4th marks Meghan Markle's 42nd birthday, and royal watchers were treated to a rare appearance by the duchess as she marked the special occasion.

Ahead of her birthday, the Duchess of Sussex was spotted alongside husband Prince Harry, 38, as the couple enjoyed a date night in Montecito, Calif. on Thursday.

The pair were all smiles as they exited Tre Lune, an Italian restaurant that's known to be a favourite of stars like Kourtney Kardashian and Ellen Degeneres.

Meghan's laid-back California style was on full display, as she was spotted wearing a figure-hugging Posse striped tube dress, a $572 CAD/$428 USD Cult Gaia clutch, and a pair of $568 CAD/$425 Emme Parsons sandals.

Retailing for $319 CAD/$239 USD, Posse's Theo Strapless Dress is currently out of stock — but you're in luck if you'd like to get your hands on the same style. It's available now for pre-order, with deliveries scheduled for October.

Theo Strapless Dress

$319 CAD/$239 USD at Posse

Billed as having "a strapless silhouette thats both elegant and timeless," the Theo Strapless Dress features a figure-hugging fit and a bold striped design that's perfect for summer.

Since the dress is on back-order, we found 10 similar styles that you can still shop now. Prices start at just $30, so you can get a royal-inspired look without having to wait — and without breaking the bank.

H&M Ribbed Dress

At just $30, this striped tank dress is a fraction of the cost of Meghan's dress, but still delivers all the style points.

$30 at H&M

SOLY HUX Women's Strapless Striped Tube Dress

For an affordable tube dress option, look to this Amazon pick that shoppers say is "cute, soft and flattering."

$42 at Amazon

Lulus Modern Classic Ivory and Black Striped Midi Sweater Dress

With fall weather around the corner, this knit sweater dress makes an excellent transitional style.

$89 at Lulus

Gap Modern Mockneck Mini Dress

This mini dress has a slim fit and a high neckline with plenty of stretch to hug your curves.

$75 at Gap

Meshki Brienne Stripe Maxi Dress

This maxi dress brings the drama, thanks to a plunging neckline and varying stripes.

$105 at Meshki

Monki Knitted Stripe Sleeveless Midi Dress

Go for an edgy look by pairing this dress with chunky boots, just like the model wearing this striped midi.

$94 at ASOS

Venus Maxi Beach Cover-Up Dress

This stylish beach coverup will be sure to turn heads on your next vacation.

$60 $65 at Venus

H&M Rib-Knit Dress

This loose-fitting dress is made from a soft viscose blend, and has side slits for easy wear.

$76 at H&M

River Island Embellished Stripe Mini T-Shirt Dress

For a more casual take on the striped dress this summer, this one has a casual T-shirt silhouette.

$85 at The Bay

Mango Striped Jersey Dress

Slip on this slinky striped dress, which features spaghetti straps and a classic racerback neckline.

$100 at Mango

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