The report said the couple plan to marry Sunday.
"Khloe and Lamar want to get married before Lamar has to go away for training, and the (basketball) season starts up (this fall,)" the insider said.
Usmagazine.com reported the ceremony is expected to take place at the Los Angeles-area home of music manager and Kardashian family friend Irving Azoff.
"They are hoping to pull together a wedding ... so they can get married and have time for a honeymoon," the source told the magazine.
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