Suveran buckle.

Posts
5,631
Likes
5,812
A plain buckle would be my assumption. The lower two in your picture look good. The branded buckle on top is 70s, more or less.
 
Posts
346
Likes
288
To my knowledge the buckle was never shown in advertisements so we'll probably never know for certain. I think I recall in the buckles thread that they were usually branded after 1948?

P1020780_zps0f314039.jpg