The news was initially reported by Zach Lowe of ESPN.
The trade comes in after Okafor requested to be bought out from the 76ers but the team denied that request.
The Sixers receive Booker, an eight-year veteran in return.
Okafor has been a disappointment for the 76ers since the team drafted him third overall in 2015, and never quite fit into what they wanted to do on the floor.More news: Conflicting Reports Emerge About Subpoena for Deutsche Bank in Trump-Russia Investigation
In Booker, Philadelphia will add a veteran forward averaging 10.1 points and 6.6 rebounds in his eighth National Basketball Association season.
Bryan Colangleo over-played his hand in a very poor way right from the time he took over as GM, the right deal was doing something about the center logjam the summer he took over the position and now he had to get what he could because the front office was the main reason Okafor's trade value took a nose dive. It will be interesting to see how he will fit with this Nets team. He's averaging just 12.5 minutes per game this season, and it was clear long ago that he wouldn't be a part of the 76ers' long-term plans. The two-year deal he signed with Brooklyn in 2016 for just over $18 million is up at the end of the 2017-18 campaign.
With the Nets struggling to hit their three-point shots, ranking 24th in three-point percentage with 35.4 percent, Stauskas can earn his minutes by doing what he does best in knocking down threes.
Stauskas has appeared in six games off of the Sixers' bench and has averaged 7.3 points, 2.1 rebounds and 1.7 assists per game during his four-year National Basketball Association career.
The 76ers are now fifth in the Eastern Conference standings, while the Nets are hovering outside playoff contention.