As of Monday afternoon, more than 12,800 Bryant items had been sold on eBay Inc since news of his death broke, including a group of 31 trading cards with his picture that sold for $US75,000 ($A111,000), according to data on the site.

That demand has caused prices to soar, according to Rick Probstein, one of the largest sellers of sports memorabilia on online auction website Ebay.

Probstein says prices increased from five to 15 times more than the original sale price.

He has also sold several Kobe Bryant basketball cards - some that were listed for more than $US10,000 ($A15,000) - along with signed basketballs, framed items and shoes.

Mentions on social media sites including Twitter and Facebook about purchasing Bryant jerseys more than doubled on Sunday following the news of his death, according to social media monitoring company Brandwatch.

There were more than 69,000 social media mentions of Bryant's NBA jersey on Sunday and Monday, the firm said, with many users sharing nostalgic stories about their first Kobe jerseys.

Bryant's book "The Mamba Mentality: How I Play" was the top-selling book on Amazon.com Inc as of midday on Monday.

On online luxury reseller The RealReal Inc, searches for Kobe Bryant sneakers spiked about 30 times higher.

The former Los Angeles Lakers was killed along with his 13-year-old daughter and seven others in a helicopter crash near Los Angeles on Sunday.

Australian Associated Press