The most coveted new ball in golf arrived at Marty Rosenblatt’s home just before Christmas, after he paid double the retail price for a half dozen on eBay . “Just to be the first kid on the block to have them,” he said.

The block, in this case, was Mirasol, a country club in Palm Beach Gardens, Fla. that costs $130,000 to join. The ball is a Costco product that retails for $1.25.

“One of my friends said, ‘How did you get them? I thought they were sold out,’” said Rosenblatt, a 68-year-old retired partner at Deloitte. “I said, ‘Yeah, I have connections.’”

Costco, the warehouse retail giant, first began selling golf balls last fall, under its Kirkland Signature brand that is affixed to a wide range of products and carries discount prices. Available for $29.99 for two dozen, the balls instantly ranked among the cheapest on the market.

But what made the balls a hot item among fanatical golfers is the revelation that, by some accounts, they perform like rivals that sell for more than twice as much.