I'm not an expert, but I did buy a '68 Malibu Sport Coupe new in 1967. I'm gonna guess your's is a '70. Am I close?
Those also look like the original Buick mag wheels. They were very distintive as I remember. I also believe that in '71 or '72, they dropped the dual headlights and went to a single for a few years before coming out with the rectangular duals and singles.