Common Pleas Judge Rose DeFino-Nastasi set sentencing for Sept. 23.
"In terms of sentencing, we're very happy that it wasn't first-degree, because that would have been life in prison," said defense attorney Thomas Burke, who argued for a voluntary-manslaughter conviction.
After shooting Austin on the edge of Cobbs Creek Golf Course, near 75th Street and Lansdowne Avenue, Wilson went home and turned his shotgun on himself, badly disfiguring his face.
Despite their 28-year age difference, Wilson and Austin lived together for eight years. But she moved out shortly after he suffered a stroke in 2008.
Depressed, heartbroken and hoping to win Austin back, Wilson used a phony $10,000 check to persuade her to meet with him the day of the murder.
Burke argued that he acted out of passion and meant only to kill himself.
Assistant District Attorney James Berardinelli told the jury of six women and six men that what Wilson did was cold-blooded, first-degree murder.
"Sympathy should play no part in your deliberations. Sympathy played no part in the death of Antoinette Austin," the prosecutor said Thursday in his closing argument.
But it appears sympathy was a factor in the verdict. One juror, a 60-year-old woman from West Philadelphia, said she did not believe Wilson deserved life in prison.
"He shot his face off. It was a hard case. It was a sad, hard case for both families," said the juror, who declined to give her name.