Inspiron n5050 upgrade problem

Hi folks. Does anyone know whether its still possible to get Windows 7 installation downloads for an Inspiron n5050 from Dell? I upgraded my dad's 2012 laptop to Windows 10 a couple of days ago, but there was a glitch and although it was running Windows 10, normal startup resulted in a black screen. Reverting to Windows 7 has left the laptop demanding the original installation disc for Windows - which didn't come with the machine. The Dell OS Recovery Tool doesn't seem to cover the laptop. Suggestions much appreciated...