To make ends meet, lifelong Lakers fan Lainey Mulligan has sold a basketball signed by Magic Johnson, a prized Kareem Abdul-Jabbar jersey and even her Kobe Bryant Nikes. But the breathtaking price of a ticket for Bryant’s final game today has her considering selling the basketball keepsake with the most sentimental value. It’s an official replica of the jersey Bryant wore when he played for Lower Merion High School in 1996. Mulligan, 25, bought it…