(Corrects paragraph 18 to say that unit sales in overall holiday spending may fall by as much as 2.5%, not that the figure applies just to toys)

By Jessica DiNapoli

NEW YORK (Reuters) -While U.S. consumers keep searching for an authentic Pop Mart Labubu, rivals are introducing their own cheaper, easier-to-find "blind box" products for the key holiday shopping season to capitalize on the craze sparked by the fuzzy mini monsters.

Hot gift lists from retailers like Walmart ( WMT ) feature a new crop of blind box figurines and trading cards, and U.S. companies including Hasbro ( HAS ) and Mattel ( MAT ) are selling versions of toys like Furby and Barbie in mystery packaging, incorporating the trend.

   A blind box toy - like Spin Master's ( SNMSF ) popular CrystaLynx dragons - generally has packaging that hides the specific product inside so shoppers keep buying until they find the one they want or collect the whole series.

Labubus stoked excitement for the trend this summer, spiking in popularity as retailers finalized their holiday plans. The "ugly-cute" dolls with toothy grins aren't widely available. They sell out in minutes and later turn up on resale sites like eBay ( EBAY ) for hundreds or thousands of dollars. Because of their cost and scarcity, they aren't on top toy lists published by major retailers and trade magazines.

But now toy aisles in holiday shopping destinations like Target ( TGT ) are crammed with goods wrapped in mystery packaging. Retailers, manufacturers and analysts expect they will be big sellers this holiday season because they're low-cost, inspire addictive shopping and appeal to adults and kids.

A Target ( TGT ) spokesperson said the retailer doubled its assortment of blind box products for the holidays, adding items from brands including Baby Three, MGA Entertainment's Miniverse, Zuru's Minibrands and Aphmau.

"It's bigger this year, and it's been getting bigger," said Juli Lennett, U.S. toy industry advisor at market research provider Circana. 

Lennett added that toy makers love it because when "people buy it, they don't buy one, they buy 10, and 30. There's the chase," she said.

Toy prices have been going up month by month, Lennett said, in part because of tariffs on China, where many of the goods are made. 

But many blind box toys remain affordable, adding to their appeal as stocking stuffers or gifts. 

Ashley Harseim, 29, of New York, is asking for a gift card to blind box retailer Miniso ( MNSO ) for the holidays. The China-based chain, which has more than 200 U.S. stores, offers figurines with characters from Peanuts, Care Bears and Disney Pixar, among others, in mystery packaging.

"The surprise is cool, it's a nice little dopamine boost and who doesn't need that now?" she said.

To treat herself, she added, she purchases blind boxes with cats inside that cost between $6 and $10. She puts them on a shelf at home.

"I look at my phone, I look at the news and then I look at my little cat, and I'm like 'aw,'" she said.

Collectibles overall, including trading cards like Pokemon, drove growth in toys in the first nine months of this year after the sector stagnated the past two, according to Circana. Circana's data, which mainly covers major retailers, does not include sales of Labubus.

But despite their popularity, the blind box toys may have a limited impact on driving overall holiday spending. Manufacturers previously marketed them year round as trinkets and impulse buys, meaning holiday sales were less important to their overall annual revenue. The last three months of the year otherwise make up 40% of the toy industry's sales, Lennett said.

Circana anticipates that unit sales for overall holiday spending - a measure of volume - may fall by as much as 2.5% during the peak shopping months of November and December.

Still, this holiday is set to be significant for specialty retailers like Miniso ( MNSO ), rival Ohku, and Canada-based Showcase, which sells authentic Labubus, and is expanding in malls and other strip centers across the country. 

Ohku introduced a new blind box series for the holidays, a spokesperson said, and is planning for its products to soon be available on Amazon.com ( AMZN ).

Showcase, which has 41 U.S. locations, has blind boxes from Sonny Angel, a competitor to Labubu, scheduled to arrive in its stores by December, said CEO Samir Kulkarni.

"Blind boxes are going to be very big," he said. "It's certainly going to be the biggest category for us in toys and collectibles that we sell. 

"Last year it was a small fraction of the sales. This Christmas will be a record Christmas for that reason," Kulkarni added.