If you own the physical Blurred Lines album (which includes the main track and “Ooo La La” as a bonus), you can rip it to FLAC using software like:
Note: The album version of "Blurred Lines" was released on the LP of the same name, but the EP file usually circulates as a promotional bundle. Robin Thicke - Blurred Lines -EP- -FLAC-
When the song became a global smash in 2013, the estate of Marvin Gaye noticed the similarities. This led to a landmark legal battle that broke traditional copyright norms: If you own the physical Blurred Lines album