The back of the one pictured above and the others have Pontonier and 600-1.

I made a stupid mistake, I only have two white banded buckles, the other two are like one in pic below.

The one in pic below states 300-1 patent no. 3393433

The others state p-535.

One member said his rear buckles were missing, but identical & like in my case, only the front white banded buckles were installed.

I bought the car in 1994 when nobody cared about or hardly knew about these cars, I see no reason as the other member here why they were tampered with, and even found a factory safety hazard warning label that stated 'seat belts loose' still attached to seat belt bolt once rear seat was removed.

I don't mind taking time away tonight to help resolve issue for my education on E Body & any future reference.